HIV Testing Blog

HIV-1 diagnosis in babies born to seropositive mothers is one of the challenges of HIV epidemics in children. A simple, rapid protocol was developed for quantifying HIV-1 DNA in whole blood samples and was used in the ANRS French pediatric cohort in conditions of prevention of mother-to-child transmission. A quantitative HIV-1 DNA protocol (LTR real-time PCR) requiring small blood volumes was developed. First, analytical reproducibility was evaluated on 172 samples. Results obtained on blood cell pellets and Ficoll-Hypaque separated mononuclear cells were compared in 48 adult HIV-1 samples. Second, the protocol was applied to HIV-1 diagnosis in infants in parallel with plasma HIV-RNA quantitation. This prospective study was performed in children born between May 2005 and April 2007 included in the ANRS cohort. The assay showed good reproducibility. The 95% detection cut-off value was 6 copies/PCR, that is, 40 copies/10(6) leukocytes. HIV-DNA levels in whole blood were highly correlated with those obtained after Ficoll-Hypaque separation (r = 0.900, P < 0.0001). A total of 3,002 specimens from 1,135 infants were tested. The specificity of HIV-DNA and HIV-RNA assays was 100%. HIV-1 infection was diagnosed in nine infants before age 60 days. HIV-DNA levels were low, underlining the need for sensitive assays when highly active antiretroviral therapy (HAART) has been given. The performances of this HIV-DNA assay showed that it is adapted to early diagnosis in children. The results were equivalent to those of HIV-RNA assay. HIV-DNA may be used even in masked primary infection in newborns whose mothers have received HAART. J. Med. Virol. 81:217-223, 2009. (c) 2008 Wiley-Liss, Inc.

The human immunodeficiency virus (HIV) is a retrovirus that causes acquired immune deficiency syndrome (AIDS). HIV can be transmitted through the exchanging of bodily fluids including blood, semen, vaginal discharge, and breast milk. Means of transmission include sexual contact with an infected person, sharing of needles or syringes with an infected person, or through blood transfusions with infected blood. Low quantities of HIV has been found in the saliva and tears of some AIDS patients; however, contact with saliva or tears has never resulted in an HIV transmission.

Healthcare workers are often exposed to the virus at work; however, it is unlikely that they will contract the virus from a patient. Since December 2001, there have been only 57 documented reports of patient-to-worker HIV transmission, mainly due to precautionary guidelines that healthcare workers follow. The main risk of transmission for healthcare workers  is through accidental needle sticks or other injury with a contaminated instrument. However, even here the risk is small. “Researchers estimate that only about 0.0-1% or healthcare workers” contract HIV from an accidental needle stick.

This low statistic can be attributed to post-exposure prophylaxis (PEP), which can be taken immediately after exposure to reduce the risk of transmission. PEP uses antiretroviral therapy (ART) to prevent transmission, but often comes with serious side effects including dizziness, fatigue, nausea, vomiting, diarrhea and more. Current antiretroviral drugs cannot cure HIV infection, nor reduce the risk of transmitting it to someone else, but they can suppress the virus to undetectable levels in some cases. It has been estimated that PEP reduces the infection rate among healthcare workers by 79%.

Post-exposure Prophylaxis should begin immediately after the exposure, seeing as how PEP is most effective when it is initiated within two t0 four hours of exposure. The specific dosage of medication depends on a couple factors including the patient’s overall health, the severity of exposure, the availability of antiretrovirals, and if the patient has any known or possible cross-resistance to any drugs. Treatment normally lasts no less than two weeks and no longer than four. Studies show that almost a quarter of those receiving PEP stop taking the medications early because of side effects. As with all forms of treatment, it is less effective if it ends early.

HIV tests should be performed after any risky sexual behavior, even if PEP was used. Immediately after HIV enters the body antibodies are produced to fight off the infection. While these antibodies cannot completely eliminate the virus, we can use their presence to see if HIV is in the blood. Most people develop detectable antibodies within two to eight weeks; however, it may take longer in some people. Most often, the enzyme immunoassay (EIA) test is used to detect HIV antibodies. If a positive result is returned it is confirmed with a follow-up test before making a diagnosis. Typically the Western blot test is used to confirm a positive HIV result. Other testing options include DNA or RNA tests, which instead of looking for antibodies actually look for genetic material of HIV. These tests can be used for early detection of HIV.

With the combination of healthcare precautions and treatment options such as PEP, we have the ability to decrease the number of patient to worker HIV transmissions drastically.

*For the complete article please refer to http://hivtestingblog.com/original-articles/

HIV post-exposure prophylaxis (PEP) is commonly used among health care workers and other individuals who believe they have recently been exposed to HIV. PEP can actually prevent HIV infection in some individuals, but according to a report in the Journal of Acquired Immune Deficiency Syndromes, even when PEP fails to prevent the infection it may still have beneficial effects.

The report involved a 38-year old gay man who reported having unprotected anal sex with multiple partners in the previous 48 hours. The patient was treated with Truvada as post-exposure prophylaxis. During his treatment the patient reported more episodes of risky sex, causing his treatment to be extended. During his treatment the patient was repeatedly tested for HIV. He received a couple negative HIV results, but after repeated exposures the patient tested HIV-positive.

The patient received three viral load tests shortly after his positive HIV test result. The viral load turned out to be extremely low, and his CD4 count was high. These results were out of the ordinary for someone with an acute HIV infection, and the patient had no HIV seroconversion symptoms. Several more tests were performed on the patient and all of them returned similar findings.

The authors of the article report that the patient’s HIV infection was weaker than usual, and that this result was most likely due to the antiretroviral therapy he was receiving.

*For the complete article please refer to http://hivtestingblog.com/original-articles/

A recent article in Morbidity and Mortality Weekly Report includes some recommendations from the Centers for Disease Control and Prevention (CDC) for use of post-exposure prophylaxis in people exposed to HIV in a nonoccupational setting.

Similar to the guidelines following occupational exposures, the CDC recommends prophylaxis beginning within 72 hours after the initial exposure with any body fluids from an HIV infected person. If 72 hours has passed after the exposure, the CDC recommends not starting prophylaxis. If the HIV status of the contact person is unknown, but the exposure has an elevated risk the CDC suggests the decision of whether to begin prophylaxis be made on a patient-to-patient basis.

Unfortunately many people are unaware that they are infected with HIV, and because of the 72 hour window period for prophylaxis these people are out of luck when they discover they were exposed. People who benefit the most from prophylaxis are those who know they have been exposed, including sexual assault victims and intravenous drug users.

Some clinicians have fears that people will use post exposure prophylaxis as a “safety net” for unprotected sex, but that is not at all it’s intended purpose.

*For the complete article please refer to http://hivtestingblog.com/original-articles/

HIV-negative persons taking antiretrovirals for postexposure prophylaxis–prevention of infection immediately after a needlestick or sexual exposure to HIV–should avoid using nevirapine except in unusual situations, according to recommendations published in the January 5 MMWR (Morbidity and Mortality Weekly Report) by the U.S. Centers for Disease Control and Prevention (CDC). Nevirapine has not been officially recommended for this use, but physicians have used it because of its rapid action and success in preventing mother to infant transmission.

A Cincinnati man, who is thought to be homeless, has been charged with assaulting Cincinnati Police Officers. His weapon of choice… spit. 48-year-old Ronald Crawford was arrested during a fight on East McMillan Street, where he spit at officers, telling them he “had AIDS”.

While the officers believe that Crawford is HIV-positive, they aren’t at any major risk, seeing as how studies have shown that HIV/AIDS is not carried in saliva. Crawford is being charged with two counts of harassment with a bodily substance — a felony.

*To view this article in it’s entirety, please visit http://hivtestingblog.com/original-articles/

Scientists have developed what some are calling a “molecular condom”. The “condom” is actually a gel that, if used correctly, could help prevent women from contracting HIV.

The gel was developed to “enable women to protect themselves against HIV without approval of their partner”. To use it the woman would only need to insert the gel a few hours before sex. The gel flows easily at the vaginal pH, and becomes more solid as the pH increases to that of semen. As the gel turns solid it traps AIDS virus particles, preventing them from infecting vaginal cells.

Due to several factors, women often have difficulty convincing their partners to use protections; however, with this new gel the woman wouldn’t even have to negotiate. It is a form of protection she can use on her own, without her partner’s knowledge.

If all goes as planned, the scientists estimate the gel will be tested in humans within three to five years, and it will be available in the years after that.

*For the complete article please visit http://hivtestingblog.com/original-articles/

Introduction

Polymerase chain reaction (PCR) has rapidly become one of the most widely used techniques in molecular biology and for good reason: it is a rapid, inexpensive and simple means of producing relatively large numbers of copies of DNA molecules from minute quantities of source DNA material–even when the source DNA is of relatively poor quality.

PCR involves preparation of the sample, the master mix and the primers, followed by detection and analysis of the reaction products. These steps are discussed below.

Sample Preparation

PCR is very versatile. Many types of samples can be analyzed for nucleic acids. Most PCR uses DNA as a target, rather than RNA, because of the stability of the DNA molecule and the ease with which DNA can be isolated. By following a few basic rules, problems can be avoided in the preparation of DNA for the PCR. The essential criteria for any DNA sample are that it contain at least one intact DNA strand encompassing the region to be amplified and that any impurities are sufficiently diluted so as not to inhibit the polymerization step of the PCR reaction.

Although any protocol is acceptable for PCR purposes, it is often best to use the fewest steps possible in DNA preparation in order to prevent accidental contamination with unwanted DNA. Usually a 1:5 dilution of the sample with water is sufficient to dilute out any impurities which may result from the purifying protocol.

The simplest method of isolating DNA from cells is as follows:

1. Cells can be obtained by using a toothpick to scrape under the fingernails, swabbing the inside of the mouth or from the roots of plucked hairs. Regardless of source, cells are resuspended in 20 ul of water. Skip to step four.
2. If you are using cells suspended in media, centrifuge at 1200- 1500Xg for 5 minutes. Resuspend the cell pellet in 1 ml of phosphate buffered saline (PBS) and repellet by spinning at 1200- 1500Xg for 5 minutes. Repeat. These PBS washes remove medium, and its inhibitory factors, from the surface of the cells. After the last wash resuspend the cell pellet in 20 ul of distilled water. Be aware that too much cell debris can inhibit the PCR reaction. If this happens, it may be necessary to further dilute the DNA sample. Go to step four.
3. For bacterial samples take a toothpick and scrape the teeth, or swab the throat, ears or between the toes. Resuspend material in 500ul of water. Freeze and thaw sample three times with vigorous shaking or vortexing between repetitions to break the bacterial cell wall. Although not all DNA will be released from the cells, there will be a sufficient quantity for PCR. Go to step four.
4. Place the sample in a 95oC heating block, or in boiling water, for 5 minutes. This step inactivates the DNase molecules that are found in the sample preparation. If left intact, DNase could clip the desired DNA template molecule into fragments which would be unsuitable for PCR. If there is very little DNA in the sample preparation, the DNA can be concentrated by ethanol precipitation. The sample is now ready for PCR.

DNA samples for PCR–regardless of preparation method–are generally run in duplicate in order to provide a control for the relative quality and purity of the original sample. Adding a small amount of DNA to the control just after the master mix step allows the detection of anything in the completed sample prep which would inhibit the PCR reaction.

Preparation of Master Mix

The Master Mix contains all of the components necessary to make new strands of DNA in the PCR process. The Master Mix reagents include:

http://www.accessexcellence.org/LC/SS/PS/PCR/PCR_technology.php

Notes on the Master Mix

The Master mix buffer is often stored as a 10X stock solution (100 mM Tris-HCL, pH 8.3, 500 mM KCL, 1.5 mM MgCl2) which is diluted to 1X for use. Both the Master mix buffer and the purified water can be stored at room temperature. Store deoxynucleotides, primers and Taq DNA polymerase enzyme at -20oC.

Although 100ul of master mix per reaction is generally used, it is possible to use as little as 25 or 50ul to save on cost of reagents. Regardless of the total volume, be certain to keep the final concentrations of reagents constant.

Master mix reagents can be optained from a variety of companies. Often the initial concentration of the reagent will differ depending on which company produced it. It is easy to figure out how much stock reagent to use by following a simple formula:

(initial concentration) X ( volume needed ) =

                                    (final concentration) X (volume of sample)

For example: I have 10X buffer, 10 mM of each nucleotide, 0.5 mM primers and Taq DNA polymerase at 5 Units/ul. I want to make one 50 ul reaction. Calculations are as follows:

10 X buffer: (10X) X (5 ul) = (1X) X (50 ul) Nucleotides: (10,000 uM) X (1 ul) = (200 uM) X (50 ul) (10mM=10,000uM) primers (500uM) X (O.1ul)= (1.0uM) X (50 ul) Since it is impossible to pipet 0.1ul accurately, a dilution needs to be made first. Add 10 ul of stock primer solution to 990 ul of water to get 5uM concentration of primers. This new primer dilution can be stored at 4oC. Calculation for 5uM stock: (5uM) X (10 ul) = (1.0 uM ) X (50 ul) Taq DNA polymerase (5Units/ul) X ( 0.25 ul) = (.025 Units/ul) X (50 ul) 2.5 Units/100ul= Since it is impossible to pipet 0.25ul accurately, a .025 Units/ul dilution needs to be made first. Add 1.25 ul stock to 3.75 ul water to get a 1.25 Units/ul concentration. Discard and make fresh with each use. Calculation for 1.25 Units/ul stock: (1.25 Units/ul) X (1 ul) = (.025 Units/ul) X (50 ul) To make the master mix for one reaction add:

• 5 ul 10X buffer
• 4ul Each nucleotide (1ul each of dATP, dCTP, dGTP, dTTP))
• 20 ul Each primer (10ul of each)
• 1 ul Taq DNA polymerase (Total volume = 30ul)
• add 15 ul of water
• 5 ul of template (Total volume = 50 ul)

If want to make 3 reactions, 3 X 50ul = 150ul. Use this number in the formula for “volume of sample.”

Primers

A primer is a short segment of nucleotides which is complementary to a section of the DNA which is to be amplified in the PCR reaction. Primers are annealed to the denatured DNA template to provide an initiation site for the elongation of the new DNA molecule. Primers can either be specific to a particular DNA nucleotide sequence or they can be “universal.” Universal primers are complementary to nucleotide sequences which are very common in a particular set of DNA molecules. Thus, they are able to bind to a wide variety of DNA templates.

Bacterial ribosomal DNA genes contain nucleotide sequences that are common to all bacteria. Thus, bacterial universal primers can be made by creating primers which are complementary to these sequences.
Examples of bacteria universal primer sequences are:
Forward 5′ GAT CCT GGC TCA GGA TGA AC 3′ (20 mer)
Reverse 5′ GGA CTA CCA GGG TAT CTA ATC 3′ (21 mer)

Animal cell lines contain a particular sequence known as the “alu gene”. There are approximately 900,000 copies of the alu gene distributed throughout the human genome, and multiple copies distributed through the genome of other animal cells, as well. Thus, the alu gene provides the sequence for a universal primer for animal cell lines. The alu primer is especially useful in that it binds in both forward and reverse directions.
The alu universal primer seqeunce is as follows:
5′ GTG GAT CAC CTG AGG TCA GGA GTT TC 3′ (26mer)

When using universal primers the annealing temperature on the thermal cycler is lowered to 40-55 degrees C.

Sometimes primer units are listed in optical density reading (OD). If this is a problem you will need to convert to molarity using the following equations: Change optical density reading of primer to molarity (uM units)-

1. N = # of primer bases
2. SIGMA 260 =~ 10,000 X N/ m X cm
3. Molecular weight =~ 330 X N
4. OD₂₆₀ / SIGMA 260 X 10⁶ = Concentration (uM)

For example- primer is 20 bases long/ OD₂₆₀ = 10.

1. N = 20
2. SIGMA 260 =~ 10,000 X 20/m X cm = 20,000/m X cm
3. molecular weight =~ 330 X 20 = 6,600
4. 10 OD₂₆₀/20,000 m^-1cm^-1 X 10⁶ = 50uM

Detection and analysis of the reaction product

The PCR product should be a fragment or fragments of DNA of defined length. The simplest way to check for the presence of these fragments is to load a sample taken from the reaction product, along with appropriate molecular-weight markers, onto an agarose gel which contains 0.8-4.0% ethidium bromide. DNA bands on the gel can then be visualized under ultraviolet trans-illumination. By comparing product bands with bands from the known molecular-weight markers, you should be able to identify any product fragments which are of the appropriate molecular weight.

MAJOR RECOMMENDATIONS

Responsibilities of Child Healthcare Providers

As part of the initial newborn evaluation, the pediatric clinician should determine whether human immunodeficiency virus (HIV) testing of the mother has been completed properly and should follow up on any outstanding laboratory values.

Pediatric clinicians should obtain testing for HIV beyond the neonatal period if the child presents with signs and symptoms of HIV disease. Testing should be performed in children who have not yet been tested when risk factors for HIV infection exist in the child or one of his/her parents.

Laboratory Tests for HIV in Newborns, Children, and Adolescents

Because positive antibody results alone do not establish infection in children younger than 18 months of age, assays to detect virus (HIV deoxyribonucleic acid [DNA] polymerase chain reaction [PCR] or viral culture) should be used for diagnosis (see Figure 1 in the original guideline document).

In children older than 18 months of age, HIV infection may be diagnosed on the basis of a positive HIV antibody test (enzyme-linked immunosorbent assay [ELISA]) and a confirmatory test, such as Western blot.

Because of the time period between infection and the development of detectable antibodies, children/adolescents exposed via sexual activity, sexual abuse/assault, or infected blood who have an initial negative test result should be retested at 1 month, 3 months, and 6 months after exposure.

Because a child with end-stage HIV disease may become HIV-antibody seronegative as a result of severe humoral immunodeficiency, children who are clinically suspected to be HIV-infected yet test HIV antibody negative should be tested by DNA PCR (or HIV culture).

Children older than 18 months of age with an indeterminate Western blot result should be retested as soon as possible. If the Western blot result remains indeterminate, the patient should be tested for HIV-2 or specific viral tests (e.g., DNA PCR) for HIV-1 should be performed.

Rapid testing and expedited preliminary test results prior to Western blot confirmation should generally be used only when immediate information is needed to determine the need for post-exposure prophylaxis in the labor/delivery, newborn, or other acute exposure settings, or when the person who is being tested is unlikely to return for a follow-up visit.

When preliminary diagnostic tests are used for expedited HIV testing, a preliminary positive test result must be confirmed with a Western blot as soon as possible.

Testing for HIV Antibody

See the original guideline document for discussions of screening tests, confirmatory testing of positive results, and rapid test assays.

Testing for HIV or Viral Components

Clinicians should test children younger than 18 months of age who are born to an HIV-infected mother for HIV using one of the following methods:

* HIV DNA PCR (preferred method)

* HIV culture (acceptable method)

Because infection can only be confirmed with two positive test results performed on samples collected at different times, a repeat sample should be obtained promptly for any child with a single positive test result.

In an infant younger than 18 months of age, HIV can be reasonably excluded with two negative HIV viral tests, one at 1 month of age or older, and the other at age 4 months or older.

Ideally, a DNA PCR should be obtained for HIV-exposed infants at each of the following time points:

* at birth

* at 2 weeks of age

* at 4 to 6 weeks of age

* at 6 to 12 weeks of age

* at 4 to 6 months of age

See the original guideline for discussions of HIV DNA PCR, HIV culture, plasma HIV RNA, and HIV antigen detection.

HIV Counseling and Testing

In New York State, written informed consent from the child’s biological parent or legal guardian must be obtained before HIV testing can be performed in children except in certain specific circumstances, such as expedited testing, newborn screening, and follow-up PCR testing, and when testing is urgently necessary to provide medical care for a life-threatening condition.

When HIV testing of a child is performed, the parents should be considered for testing as well.

If a child is found to be perinatally HIV infected, his/her siblings also should be tested.

If HIV infection is newly diagnosed in a woman, all of her children should be strongly considered for testing, even if they are asymptomatic.

Pre-Test Counseling

The clinician should counsel the child’s parent or guardian or the child/adolescent with capacity to consent prior to HIV testing (see Table 2 in the original guideline document).

In New York State, a minor’s right to consent for or refuse HIV testing is based on his/her capacity to understand, without regard to chronological age, what an HIV antibody test actually tests for, the implications/consequences of being HIV infected, and why he/she is at risk for HIV.

The clinician should arrange for follow-up visits at the time of testing and should note in the patient’s medical record that counseling was provided and written consent was obtained when required.

When rapid testing is obtained and will yield a preliminary result during the visit, the clinician should first ensure that the patient/parent is emotionally able to receive a positive result and that mental health services are available for patients receiving a positive result.

Obtaining Consent

See the original guideline document for a discussion New York State laws on obtaining consent for HIV testing in children and adolescents for HIV testing.

Post-test Counseling

Counseling after a Patient Receives a Positive Test Result

Positive HIV test results should be presented in person to the appropriate individual (patient, parent, or guardian). A clinician should not communicate results to a patient or family member by telephone or mail.

Clinicians must respect an adolescent’s right to confidentiality concerning HIV status.

The clinician should explain the test results and should provide general information about available treatment.

The clinician should discuss the implications of the HIV Reporting/Partner Notification law (refer to the section “HIV Reporting and Partner Notification” below).

The clinician should provide or arrange for necessary referrals for treatment and supportive services.

The clinician should discuss methods of risk reduction and advise the family to inform medical personnel of the child’s HIV status during any medical care visit.

Counseling After the Patient Receives a Negative Test Result

When telling a patient that his/her test result is negative, the clinician should educate the patient on how to reduce the risk of transmission in the future.

HIV Reporting and Partner Notification

Since June 2000, New York State has required HIV reporting and partner notification for all confirmed positive HIV tests (unless testing occurred at an anonymous site) and HIV-related tests.

During pre-test counseling, parents/children should be informed that if their HIV test result is positive, their names will be reported to the New York State Department of Health.

Parents/children should be informed during pre-test counseling that if they provide the names of sexual or needle-sharing partners, the provider is required to report these names to the State Health Department. They should also be informed that if the test results are positive, their partners will be notified that they have been exposed to HIV.

All sexually active HIV-infected adolescents should be informed about the importance and benefits of notifying partners of their possible exposure to HIV.

Adolescents who are undergoing HIV testing should be questioned regarding the potential for domestic violence if their partners were notified. If domestic violence is a concern, partner notification should be deferred until the risk of harm to the patient (or one close to the patient, e.g., child) is eliminated.

HIV Testing of Older Children and Adolescents With the Capacity to Consent

Clinicians should be knowledgeable about New York State laws pertaining to adolescent consent and confidentiality and should educate their patients about these laws (see the National Guideline Clearinghouse (NGC) summary of the New State Department of Health guideline Identification and Ambulatory Care of HIV-exposed and -infected Adolescents).

In New York State, older children and adolescents who are judged capable of understanding the informed consent process may give written informed consent for HIV testing.

Parents cannot be informed of their child’s HIV test results without the explicit consent of the child or adolescent who is deemed capable of providing consent.

Ideally, HIV testing of older children and adolescents should occur in a comprehensive care setting that provides social support, ancillary services, and ongoing health care.

HIV Testing in Children in Foster Care

Within 5 days of entering the foster care system, all children must be assessed for capacity to consent for HIV testing. If a child is determined not to have capacity to consent, an HIV risk assessment must also be completed within the first 5 days of entering foster care. Children already in foster care must be assessed for HIV risk factors at least 60 days prior to their next scheduled periodic medical examination. If it is determined that a child may have the capacity to consent, an assessment of capacity to consent must be made and documented by authorized foster care agency staff within 30 days of the child’s entry into foster care. An HIV risk assessment must also be completed within this timeframe.

If one or more risk factors are present, a child in foster care should be offered HIV testing, or if the child lacks capacity to consent, he/she should be tested for HIV infection.

Adolescents and older children in foster care with the capacity to consent for HIV testing have the right to either consent for their own test or refuse testing.

For the commplete article, please refer to http://www.guidelines.gov/summary/summary.aspx?doc_id=6834

Scientists at the University of North Carolina Chapel Hill (UNCCH) have opened up many possibilities into treatment of HIV by decoding the entire structure of the HIV genome. Until now, only small portions of the genome could be studied; however, by using their own technology they were able to view the genome aerially. They discovered that the HIV genome is gigantic, consisting of two strands containing ten-thousand blocks each.

According to Kevin Weeks, the professor who led the study, the HIV genome is loaded with RNA structures that control the virus’ behavior. The genomes for hepatitis C, polio, and influenza are also RNA programmed, so by using the same technology we may gain a better insight into these diseases and also vice-versa.

New anti-viral drugs that result from this discovery most likely won’t be available for another couple years; however, this new insight may lead HIV/AIDS researchers to explore possibilities that weren’t considered before.

*For the complete article please visit http://www.hivtestingblog.com/original-articles/

Health Horizons, an East Texas health care organization, has seen more HIV-positive people this year than it did all last year. As of July, eight people out of 800 had tested positive; whereas for all of 2008 they had only six positives out of more than 1,000 testers. The majority of these HIV-positive people were African-American men. Health Horizon’s Executive Director, Wilbert Brown, is associating the spike in numbers to their effective advertising which targets high-risk groups.

For the complete article, please visit http://hivtestingblog.com/original-articles/

A report from the Chicago Public Health Department (CDPH) has found higher rates of HIV infection in Black men who have sex with men (MSM) than in white or Latino MSM.

The report comes from a survey that was conducted across all of Chicago, in places where MSM often congregate. These places include gay bars/clubs, bathhouses, social organizations, and others. Participants were asked about their sexual preferences and practices, and then also tested for HIV antibodies. Although other surveys similar to this have been performed in the past, this was the first where the people were actually tested.

The survey found that African Americans had around three times the prevalence rate of HIV than that of white and Latino participants. However, the survey also found that Black MSM do not necessarily engage in riskier behavior, and usually engage less frequently than whites or Latinos. Half of the people who tested positive in the survey were unaware of their HIV-positive status. Once again, Black MSM had higher rates in this category. 66% of Black HIV-positive MSM did not know their status, 50% of Latino HIV-positive MSM, and 23 % of white HIV-positive MSM did not know their status.

While many efforts are being made to address this epidemic, such as condom distribution and affordable HIV testing, much more still needs to be done.

* For the complete article, please visit http://hivtestingblog.com/original-articles/

French researchers have identified a new human immunodeficiency virus, the first derived from gorillas, a report said Monday.

The three previous HIV variants came from chimpanzees. The new findings indicate that gorillas, in addition to chimpanzees, are likely sources of HIV, the researchers concluded in a report published in the weekly Nature Medicine journal.

The new virus, called RBF 168, was detected in a 62-year-old woman who moved to Paris, France, from the western Africa nation of Cameroon, the report says. She tested positive for HIV in 2004, and researchers led by Jean-Christophe Plantier identified the virus as being closely related to a recently discovered simian immunodeficiency virus (SIV).

The new gorilla virus “has many of the biological properties necessary for human infection,” the report says.

“The human case described here does not seem to be an isolated incident, as before coming to Paris the subject had lived in the semiurban area of Yaounde, the capital of Cameroon, and reported no contact with apes or bush meat,” the researchers said.

That would indicate that the woman contracted the virus from another human.

The significance of the latest findings is difficult to determine without more information, said Robert C. Gallo, who co-discovered HIV in 1984.

“It’s yet to be known,” Gallo said. “It could be zero. … Let’s see a more full report on this individual and let’s see wider testing.”

Even if the new variant proves lethal, it’s not likely to increase AIDS infections, said Gallo, director of the Institute of Human Virology at the University of Maryland School of Medicine. There are so many HIV variations, he said, that one more is not likely to make a difference.

The new virus is difficult to detect by conventional tests because it is not closely related to the other three HIV variants.

“This demonstrates that HIV evolution is an ongoing process,” co-researcher David Robertson of the University of Manchester said in a release. “The virus can jump from species to species, from primate to primate, and that includes us; pathogens have been with us for millions of years and routinely switch host species.”

HIV can lead to acquired immunodeficiency syndrome, which attacks the body’s immune system, giving rise to lethal infections. Patients diagnosed with HIV can take medications to delay or stop HIV from developing into AIDS. There are 33 million confirmed cases of AIDS worldwide.

The unnamed woman has no signs of AIDS and remains untreated, Nature Medicine said.

The most likely explanation for the emergence of the new virus is gorilla-to-human transmission, though researchers say they cannot rule out the possibility that the chimpanzee SIV gave rise to the new strain “either indirectly by transmission to gorillas and then to humans or directly by transmission to humans and also to gorillas.”

Researchers said they don’t know how widespread the virus is among humans.

“The human prevalence of this new lineage remains to be determined,” the report says, adding that “it could be circulating unnoticed in Cameroon or elsewhere.”

Western Central Africa bears close watching, the researchers suggest.

“In conclusion, our findings indicate that gorillas, in addition to chimpanzees, are likely sources of HIV-1,” the report states. “The discovery of this novel HIV-1 lineage highlights the continuing need to watch closely for the emergence of new HIV variants, particularly in western central Africa, the origin of all existing HIV-1 groups.”

Co-researcher Robertson noted that the new virus may not be restricted to Africa.

“It also highlights how human mobility can rapidly transfer a virus from one geographical location to another as has been dramatically evident with the recent emergence of swine flu,” he said.

For the complete article, please refer to www.cnn.com

Gorillas have been found, for the first time, to be a source of HIV.

Previous research had shown the HIV-1 strain, the main source of human infections, with 33m cases worldwide, originated from a virus in chimpanzees.

But researchers have now discovered an HIV infection in a Cameroonian woman which is clearly linked to a gorilla strain, Nature Medicine reports.

A researcher told the BBC that, though it was a new type of HIV, current drugs might still help combat its effects.

A 62-year-old woman living in Paris tested positive for a new strain of HIV. Before this, it was thought that all strains of HIV-1 were passed to humans by chimpanzees; however, this new strain is thought to have derived from gorillas.

The woman, originally from the capital of Cameroon, Yaounde, tested positive for HIV in 2004 and has not yet shown any signs of AIDS. How she contracted this new strain of HIV is still unknown. The woman claims to have had no encounters with live gorillas or bushmeat.

This new discovery presents many new questions, and also other possibilities that have been investigated before. How many people are infected with this new strain is hard to tell, but researchers will definitely be looking into possibly even more strains of HIV.

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A new strain of the virus that causes AIDS has been discovered in a woman from the African nation of Cameroon.
It differs from the three known strains of human immunodeficiency virus and appears to be closely related to a form of simian virus recently discovered in wild gorillas, researchers report in Monday’s edition of the journal Nature Medicine.
The finding “highlights the continuing need to watch closely for the emergence for new HIV variants, particularly in western central Africa,” said the researchers, led by Jean-Christophe Plantier of the University of Rouen, France.
The three previously known HIV strains are related to the simian virus that occurs in chimpanzees.
The most likely explanation for the new find is gorilla-to-human transmission, Plantier’s team said. But they added they cannot rule out the possibility that the new strain started in chimpanzees and moved into gorillas and then humans, or moved directly from chimpanzees to both gorillas and humans.
The 62-year-old patient tested positive for HIV in 2004, shortly after moving to Paris from Cameroon, according to the researchers. She had lived near Yaounde, the capital of Cameroon, but said she had no contact with apes or bush meat, a name often given to meat from wild animals in tropical countries.
The woman currently shows no signs of AIDS and remains untreated, though she still carries the virus, the researchers said.
How widespread this strain is remains to be determined. Researchers said it could be circulating unnoticed in Cameroon or elsewhere. The virus’ rapid replication indicates that it is adapted to human cells, the researchers reported.
Their research was supported by the French Health Watch Institute, the French National Agency for Research on AIDS and Viral Hepatitis and Rouen University Hospital.
A separate paper, also in Nature Medicine, reports that people with genital herpes remain at increased risk of HIV infection even after the herpes sores have healed and the skin appears normal.
Researchers led by Drs. Lawrence Corey and Jia Zhu of the Fred Hutchinson Cancer Research Center found that long after the areas where the herpes sores existed seem to be clear, they still have immune-cell activity that can encourage HIV infection.
Herpes is marked by recurring outbreaks and has been associated with higher rates of infection with HIV. It had been thought that the breaks in the skin were the reason for higher HIV rates, but a study last year found that treatment of herpes with drugs did not reduce the HIV risk.
The researchers tested the skin of herpes patients for several weeks after their sores had healed and found that, compared with other genital skin, from twice to 37 times more immune cells remained at the locations where the sores had been.
HIV targets immune cells and in laboratory tests the virus reproduced three to five times faster in tissue from the healed sites as in tissue from other areas.
“Understanding that even treated (herpes) infections provide a cellular environment conducive to HIV infection suggests new directions for HIV prevention research,” commented Dr. Anthony S. Fauci, director of the National Institute of Allergy and Infectious Disease.
That study was funded by the National Institutes of Health and the Tietze Foundation.

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