Transmissibility of human immunodeficiency virus in haemophilic and non-haemophilic children living in a private school in France

Expert consensus statement on the science of HIV in the context of criminal law

INTRODUCTION

Globally, prosecutions for non-disclosure, exposure or transmission of HIV frequently relate to sexual activity, biting, or spitting. This includes instances in which no harm was intended, HIV transmission did not occur, and HIV transmission was extremely unlikely or not possible. This suggests prosecutions are not always guided by the best available scientific and medical evidence.

DISCUSSION

Twenty scientists from regions across the world developed this Expert Consensus Statement to address the use of HIV science by the criminal justice system. A detailed analysis of the best available scientific and medical research data on HIV transmission, treatment effectiveness and forensic phylogenetic evidence was performed and described so it may be better understood in criminal law contexts. Description of the possibility of HIV transmission was limited to acts most often at issue in criminal cases. The possibility of HIV transmission during a single, specific act was positioned along a continuum of risk, noting that the possibility of HIV transmission varies according to a range of intersecting factors including viral load, condom use, and other risk reduction practices. Current evidence suggests the possibility of HIV transmission during a single episode of sex, biting or spitting ranges from no possibility to low possibility. Further research considered the positive health impact of modern antiretroviral therapies that have improved the life expectancy of most people living with HIV to a point similar to their HIV-negative counterparts, transforming HIV infection into a chronic, manageable health condition. Lastly, consideration of the use of scientific evidence in court found that phylogenetic analysis alone cannot prove beyond reasonable doubt that one person infected another although it can be used to exonerate a defendant.

CONCLUSIONS

The application of up-to-date scientific evidence in criminal cases has the potential to limit unjust prosecutions and convictions. The authors recommend that caution be exercised when considering prosecution, and encourage governments and those working in legal and judicial systems to pay close attention to the significant advances in HIV science that have occurred over the last three decades to ensure current scientific knowledge informs application of the law in cases related to HIV.

Genetic relatedness of human immunodeficiency virus-1 (HIV-1) strains in a 12-year-old daughter and her father in a household setting

Modalities of intra-familial transmission of HIV-1 are not always clear. Here we describe an uncommon case of HIV transmission in a family setting, analyzed using clinical, epidemiological and nucleic-acid-based methods, and assess risk factors for intrafamilial transmission of HIV-1 infection. All sequences from the father and the daughter were grouped in the same cluster with a 100 % bootstrap value, which means that the father and his daughter were infected with highly homologous CRF01_AE. The diversity of genetic clones between env and pol genes was insignificant (p > 0.05). Moreover, the results of analysis of drug-resistance-associated mutation positions of the two viral isolates were almost identical, indicating that both were susceptible to the first-line anti-HIV drugs prior to the initiation of antiretroviral treatment (ART), and this presented additional evidence of a high similarity between the two family members' HIV-1 quasispecies. In this family, HIV-1 isolates from a father and his daughter had very highly genetic relatedness. By combining their clinical histories, we could draw the conclusion that the daughter was probably infected via contact with her father's blood or other body fluids, but no obvious transmission route was found, suggesting that HIV-1 infection in similar household settings should be taken into consideration whenever the origin of HIV-1 infection cannot be identified.

Identification of human immunodeficiency virus-1 (HIV-1) transmission from a 29-year-old daughter to her mother in Shanghai, China

BACKGROUND AND METHODS

Routes of intrafamilial transmission of HIV-1 are not always clear. Here, we describe transmission to a mother from her 29-year-old daughter within a family setting through clinical, epidemiological and molecular evidence. We evaluated the risk factors for intrafamilial transmission of HIV-1 infection through qualitative epidemiology following pol and env gene sequencing and phylogenetic analysis.

RESULT

The nucleotide sequences of the pol and env genes of the two strains from the two patients in the family were 99 % and 100 % identical, respectively, and they clustered with CRF07_BC, which includes the main recombinant strains in Shanghai, China. The diversity of genetic clones between the env and pol genes was insignificant (p > 0.05). The drug-resistance-associated mutation positions of the two viral strains were basically similar and indicated that both were susceptible to the first-line anti-retroviral drugs including zidovudine (AZT), lamivudine (3TC), efavirenz (EFV) and nevirapine (NVP) prior to the initiation of highly active antiretroviral treatment (HAART), providing additional evidence of a close similarity between the quasispecies of the two family members.

CONCLUSION

In this family, the two strains of the virus, isolated from the mother and her adult daughter, had very high homology. In the context of their clinical histories, we can make a conclusion that the mother was infected by the virus in her daughter's blood or other body fluids, but no overt transmission route has been clarified. This investigation also suggested that intimate personal exposure in the same household can contribute to HIV-1 transmission and underscores the need to educate persons who care for or are in contact with HIV-infected persons in household settings where such exposures may occur.

Transmission of Drug-Resistant HIV-1 from an Infected Individual to a Caregiver

Objective

To describe a suspected case of intrafamilial transmission of drug-resistant HIV-1 from an infected individual to his caregiver.

Methods

HIV-1 protease, reverse transcriptase, nef and gp41 DNA sequences were determined from plasma samples after RNA extraction and nested RT-PCR. Phylogenetic trees were generated using neighbour-joining methods.

Results

HIV-1 infection was diagnosed in an individual (index) following the death of her HIV-infected adopted son (source). The index case cared for her son in the 9 months prior to his death. No obvious instances of contact with bodily secretions or other traditional risk factors for HIV transmission were identified, although the index case had mild eczema. At time of death, the source case's HIV plasma viral load was >1,000,000 HIV copies/ml. Genotyping of the protease and reverse transcriptase of both the source and index samples revealed similar drug-resistance mutations despite the index case being antiretroviral-naive. Both source and index V3 genotypes were consistent with syncytium-inducing virus. The mean pairwise amino acid identity between the source and index samples was 97.0%, 99.2%, 92.6% and 94.6% in protease, reverse transcriptase, nef and gp41, respectively. The source and index sequences clustered together on phylogenetic trees when compared with 50 randomly selected sequences from British Columbia.

Conclusion

Although exceptionally rare, our case demonstrates transmission of drug-resistant HIV-1 from an infected individual to his caregiver in the absence of traditional risk factors. It should be noted that the source had a very high viral load during the terminal phase of his illness.

Sampling irregularities, or why the present estimate for risk of HIV casual transmission is probably an underestimate

Updating the list of casual transmission studies yielded a minor revision of the recently reported estimate of the risk of HIV casual household transmission, estimating it as 0.3% per year of contact. A meta-analysis of the studies used to calculate this risk indicated that the estimated risk is probably an underestimate for four main sampling irregularities: (a) The studies employed samples which were based on selective non-participation of subjects including refusals and unlocatable subjects at average rates of 36% and 14%, respectively; (b) only 17% of the studies reported full numerical details of the population studied; (c) the studies were based on unjustified exclusions of subjects by the investigators at an average rate of 31%; (d) the sampling of studies cited in the transmission studies is consistent with the hypothesis that the studies were biased against reporting cases of casual transmission. In the 13% of the studies that reported full details of exclusions, the average rate of all exclusions combined was 84%. Since it is likely that cases of casual transmission were mostly included among the exclusions, this may have resulted in an unrepresentatively low frequency of casual infection among the 16% that were left to be studied.

Casual household transmission of human immunodeficiency virus

The consistent conclusion of many studies and reviews is that there is no evidence for casual household transmission of human immunodeficiency virus (HIV). The objective of this study was to analyze the evidence for casual household transmission. Data were obtained from published studies identified by computer searching, bibliographies, and consultations with experts. The analysis indicated that casual household transmission is a route of HIV transmission.

Genetically related human immunodeficiency virus type 1 in three adults of a family with no identified risk factor for intrafamilial transmission

A small number of cases of human immunodeficiency virus (HIV) infection have been reported in individuals with no identified risk factors for transmission. We report on the seroconversion of the 61-year-old mother and the subsequent finding of HIV seropositivity in the 66-year-old father of a 31-year-old AIDS patient. Extensive investigation failed to identify any risk factor for intrafamilial transmission. We conducted a genetic analysis and determined the amino acid signature patterns of the V3, V4, and V5 hypervariable domains and flanking regions in the HIV-1 gp120 env gene of 26 clones derived from proviral DNA in peripheral blood mononuclear cells of the members of the family. env sequences of the viruses isolated from the patients were compared with sequences of HIV-1 subtype B viruses from Europe and local field isolates. Phylogenetic analysis revealed that the sequences of the viruses isolated from the patients were genetically related and formed an intrafamilial cluster of HIV-1 distinct from other subtype B viruses. Interindividual nucleotide variability in the C2-V3 and V4-C4-V5 domains ranged between 1.2 and 5.0% and between 2.2 and 7.5%, respectively, whereas divergence between HIV strains from the patients and control viral strains ranged from 6.6 to 29.3%. The amino acid signature patterns of viral clones from the three patients were closely related. In the C2-V3 region, two minor clones derived from the son's virus showed less nucleotide divergence (mean, 3.5 and 3.9%) than did the clones derived from the viruses of both parents or the seven other predominant clones derived from the virus from the son (mean, 5.4%). The top of the V3 loop of the last two clones and of all viral clones from the parents exhibited an unusual GPGG sequence. This is the first report of genotypic relatedness of HIV-1 in three adults of the same family in the absence of identified risk factor for transmission between the members of the family. Our findings suggest that atypical transmission of HIV may occur.

Lack of evidence of transmission of HIV-1 to family contacts of HIV-1 infected children

Although a number of studies have documented that casual household contact does not result in the transmission of HIV, isolated cases of person-to-person transmission have been reported. We report a study of household transmission in which the families were unaware the children were infected with HIV and thus took no precautions to prevent transmission. Twenty-two family members of nine transfusion-associated HIV-infected children were studied for transmission of HIV in households. There was a total of 174 person-year of household exposure; 76 of these exposure years were before the diagnosis of HIV infection in the index child. All family members tested negative for HIV by ELISA. Sharing household facilities, and interactions with the infected child including kissing, bathing, sleeping with, and helping to bathe, dress, and eat, did not result in transmission. Interactions that could theoretically result in person-to-person transmission occurred in these households such as caring for nose bleeds, biting, and home health care procedures. The findings of this and other studies support the participation of HIV-infected infants and children in out-of-home care programs. It remains prudent, however, to observe current recommendations for prevention of HIV-1 for all individuals regardless of whether HIV status is known.

Infection and AIDS in adult macaques after nontraumatic oral exposure to cell-free SIV

Unprotected receptive anal intercourse is a well-recognized risk factor for infection with human immunodeficiency virus-type 1 (HIV-1). Isolated human case reports have implicated HIV-1 transmission by oral-genital exposure. Adult macaques exposed nontraumatically to cell-free simian immunodeficiency virus (SIV) through the oral route became infected and developed acquired immunodeficiency syndrome (AIDS). The minimal virus dose needed to achieve systemic infection after oral exposure was 6000 times lower than the minimal dose required to achieve systemic infection after rectal exposure. Thus, unprotected receptive oral intercourse, even in the absence of mucosal lesions, should be added to the list of risk behaviors for HIV-1 transmission.

Risk of acquiring AIDS from salivary exchange through cardiopulmonary resuscitation courses and mouth-to-mouth resuscitation

In summary, the risk of transmission of HIV and other infectious diseases by saliva during CPR training practice is extremely low because of low infectious virus titers and properties of saliva that inhibit HIV. However, it is necessary to perform decontaminations of mannequins, by application of a suitable disinfectant and by a mechanical wipe-down with a sponge, to cleanse the external buccal area of the mannequin after contact with each CPR trainee. For health care and public safety professionals training and performance of MTM ventilation during CPR should be carried out with barrier devices such as the bag-valve-mask or face shield. Guidelines and standards of the AHA, American Red Cross, and the CDC for prevention of infection during CPR and emergency cardiac care are more fully available elsewhere. If the recommended procedures are followed, the risk of acquiring HIV from saliva during MTM should be extremely low.

Transmission from one child to another of human immunodeficiency virus type 1 with a zidovudine-resistance mutation

BACKGROUND AND METHODS. We describe a child who apparently acquired human immunodeficiency virus type 1 (HIV-1) infection in the home setting. The suspected source of infection was a child with the acquired immunodeficiency syndrome who had received zidovudine and whose virus contained a mutation associated with in vitro zidovudine resistance. The children were born to different HIV-1-infected mothers, but they lived in the same home between the ages of two and five years. Child 1 was infected perinatally; Child 2 was not and was repeatedly found to be seronegative. Child 2 was examined because of acute lymphadenopathy and had seroconverted to HIV-1 positivity. HIV-1 proviral DNA was amplified from peripheral-blood mononuclear cells and subjected to sequence analysis. Sequences from Child 2 were compared with those from Child 2's mother, Child 1, and local HIV-1-infected control children.

Attitudes of BCLS instructors about mouth-to-mouth resuscitation during the AIDS epidemic

We surveyed 5,823 American Heart Association Virginia Affiliate basic cardiac life support (BCLS) instructors to assess the impact that the acquired immunodeficiency syndrome (AIDS) epidemic has had on their attitudes, beliefs, and behaviors with respect to the training and performance of mouth-to-mouth (MTM) ventilation. The response rate by those whose mail survey could be delivered to a valid address was 41% (women, 63%; men, 37%; mean age, 38 +/- 1 years; health care providers, 87%; laypersons, 11%; and public safety workers, 2%). Of those surveyed, 49% had performed CPR within the past three years. Of these, 40% reported having hesitated to provide MTM ventilation at least once. Of those who had hesitated, more than one half identified fear of exposure to disease as the reason for their hesitation. Forty percent of all respondents had witnessed another provider hesitate to provide MTM ventilation. When presented with mock rescue scenarios, the majority of respondents indicated that they would not perform or would hesitate to perform MTM ventilation on most adult strangers. More than half felt that there was some risk of contracting AIDS from ventilating a manikin, and 71% said that their attitudes about providing CPR to strangers had changed as a result of the AIDS epidemic. We conclude that concern about AIDS appears to be adversely affecting the attitudes, beliefs, and self-reported behaviors of BCLS instructors in Virginia regarding the use of MTM ventilation on strangers.

Lack of transmission of HIV to sexual and non-sexual contacts to HIV seropositive haemophiliacs following preventive information

In order to evaluate the risk of HIV transmission to sexual and non-sexual contacts to seropositive haemophiliacs, HIV antibodies, p24 antigen, immunoglobulin levels and lymphocyte subsets were analyzed in a cohort of Swedish haemophiliac families to 19 patients who seroconverted in 1980-82. As controls served contacts to 26 seronegative haemophiliacs. A total of 77 contacts were investigated. Except for 3 sexual partners who had seroconverted before 1985 no signs of HIV infection were detected. It was concluded that no HIV transmission occurred to household contacts of seropositive haemophiliacs and that transmission to heterosexual partners not appeared since 1985 when the patients and their families were informed about the risk of infection.

Antibodies to the nef protein and to nef peptides in HIV-1-infected seronegative individuals

The silent period that follows infection by the human immunodeficiency virus (HIV-1) and precedes seroconversion remains a problem for the screening of blood supply, and knowledge about the mechanism involved in the maintenance of latency is only fragmentary. Using purified nef recombinant protein and six synthetic nef peptides, antibodies to the product of an HIV-1 regulatory gene, the negative regulatory factor (nef) involved in maintenance of proviral latency, were detected by Western blot and radioimmunoassay techniques in HIV-1-seronegative, viral antigen-negative, and virus culture-negative individuals at risk for HIV infection. This antibody response to nef was correlated in eight individuals with the detection of HIV-1 proviral DNA by oligonucleotide hybridization, following enzymatic amplification of HIV DNA in peripheral blood mononuclear cells. Such latent HIV infections have now been followed for up to 6 or 10 months in five individuals. In addition, retrospective and prospective analysis of HIV-1-seropositive individuals have shown (1) antibodies to nef preceding seroconversion, and (2) the persistence of antibodies to nef and of HIV-1 proviral DNA in a case of spontaneous complete HIV-1 seronegativation. Since DNA amplification cannot be currently considered for routine use, screening for anti-nef antibodies followed by confirmation by DNA amplification could represent a basis for new diagnostic strategies. Beyond their diagnostic implications, these findings, suggesting that regulatory genes of the HIV-1 provirus can be expressed prior to the initiation of virion synthesis, may also be applicable in the design of alternative vaccines against the acquired immunodeficiency syndrome.

A longitudinal study of serum beta 2-microglobulin levels in haemophilia

Serum beta 2-microglobulin (beta 2-m) levels were measured in 75 adults with haemophilia A. Beta 2-microglobulin was found to be significantly elevated in haemophiliacs compared with the non-haemophiliac population. There was a greater rise in beta 2-m in HIV antibody-positive haemophiliacs. No further significant increase occurred in the subgroup with HIV-related disease but all these patients had beta 2-m levels greater than or equal to 3 mg/l. Over the study period of 18 months no significant increase in beta 2-m was documented in either HIV antibody-negative or -positive groups. Beta 2-microglobulin was elevated in HIV antibody-negative subjects with raised transaminase levels. No correlation was found between beta 2-m and the amount of factor VIII concentrate infused, T-cell subsets, thrombocytopenia or age. It is concluded that probable reasons for elevated beta 2-m levels in haemophiliacs include infection with HIV and other viruses, chronic liver disease, and repeated antigenic challenge from multiple infusions of factor VIII. The role of serial measurement of beta 2-m in haemophiliacs with a view to predicting the onset of HIV-related disease warrants further study.

Memorandum on the infections hazards of the common communion cup with especial reference to AIDS

Bacteriological studies on the communion cup have shown that there is a low level of contamination with mouth organisms on the rim. The death rate of bacteria on the cup surface would not be significant, but the wine had a bactericidal effect on most but not all organisms tested. However droplets of saliva did not readily mix with the wine. In considering the spread of AIDS, extensive studies of people infected with human immunodeficiency virus (HIV) in hospital or at home have shown that the established routes of spread are the injection of blood or blood products, sexual intercourse or at birth. There are only very rare examples of spread by other means. The virus is rarely isolated from the saliva and a study of homosexuals indulging in oral sexual intercourse suggests that it is very poorly infectious when taken into the mouth or swallowed. It is concluded that the risk of transmission of HIV by the common communion cup can be neglected under ordinary circumstances. Suggestions are made for improving the hygiene of the communion service which may be useful under special circumstances: there is no evidence that disease is spread in this way under normal conditions.

The hazard of infection from the shared communion cup

Interest and concern that the shared communion cup may act as a vehicle for indirectly transmitting infectious disease was reawakened when the human immunodeficiency virus (HIV) was detected in the saliva of infected persons. Bacteriological experiments have shown that the occasional transmission of micro-organisms is unaffected by the alcoholic content of the wine, the constituent material of the cup or the practice of partially rotating it, but is appreciably reduced when a cloth is used to wipe the lip of the cup between communicants. Nevertheless, transmission does not necessarily imply inoculation or infection. Consideration of the epidemiology of micro-organisms that may be transmitted via saliva, particularly the herpes group of viruses, suggests that indirect transmission of infection is rare and in most instances a much greater opportunity exists for direct transmission by other means. There is substantial evidence that neither infection with hepatitis B virus nor HIV can be transmitted directly via saliva so that indirect transmission via inanimate objects is even less likely. No episode of disease attributable to the shared communion cup has ever been reported. Currently available data do not provide any support for suggesting that the practice of sharing a common communion cup should be abandoned because it might spread infection.

HIV infection in children: sizing up the paediatric problem

Cases of paediatric AIDS have increased each year in the USA, as the disease has spread to the heterosexual community. In the USA the geographic distribution of perinatal AIDS cases mirrors the distribution of cases in women. To date, 503 HIV antibody positive women have been reported in the UK. It is likely that the increasing number of seropositive women will be reflected in an increase in the number of reports of perinatal HIV infection and AIDS. Although screening of blood donors and blood products has stopped further increase in infections from this route, as transfusion-infected children become symptomatic the burden on paediatric services will increase.

Immunoglobulin levels in haemophiliacs at HIV seroconversion and during follow up

Immunoglobulins and aminotransferases were followed in 66 haemophilia patients and 13 von Willebrand patients over a six-year period. The results were correlated to HIV serology and lymphocyte subsets. Elevated IgG levels were found in 29/53 patients with haemophilia A, 2/13 with haemophilia B and in 0/13 with von Willebrand's disease. Elevated IgA and IgM levels were seen in 20% and 27% of the patients respectively, with a distribution similar to the elevated IgG levels, except that elevated IgA and IgM levels were also seen in 4/13 patients with von Willebrand's disease. Patients with HIV antibodies had significantly higher immunoglobulin levels than seronegative patients, and this elevation occurred in connection with seroconversion in the majority of the former. The IgG levels could not be correlated to the T4 cell count, but there has been a trend to less clinical symptoms related to HIV infection among those with stable IgG levels during the past few years. No correlation was found between elevated IgG levels and the aminotransferase levels, nor was any correlation found with the amount of blood coagulation factor concentrate given to the patients. The elevation of immunoglobulins observed in our haemophiliacs is multifactorial, but HIV infection is maybe the most important mechanism. The longitudinal IgG pattern may contribute to the prediction of the clinical outcome of this infection.