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J M McAnerney

Publications and source records attributed to J M McAnerney.

At least 19 recordsLinked to original sources
PubMed2002

Regional perspectives on influenza surveillance in Africa.

Africa possesses little capacity for influenza surveillance-Senegal and South Africa being the only countries in the WHO African region who regularly pursue active surveillance and characterize influenza isolates. South Africa has three sites-in Cape Town, Durban and the largest in Johannesburg at the National Institute for Virology (NIV). The NIV antigenically and molecularly characterizes influenza viruses isolated from specimens provided by a sentinel network of approximately 50 clinical sites. This information, together with the isolates themselves are supplied to WHO International Influenza Centres in London and Melbourne. In addition, proxy markers of influenza severity such as school absenteeism and doctor/clinic visits are monitored to assess the severity of epidemics. Although, influenza exacts a heavier toll of the illness burden in developing countries already beset with underlying chronic medical conditions and also has a more severe impact on economies largely dependent on single income earners and subsistence farmers, influenza surveillance and vaccination awareness is woefully lacking on the African continent, and this urgently needs to be remedied.

Animals↗
PubMed2001

Seroprevalence to polio in personnel at a virology institute.

OBJECTIVES: To determine the level of immunity to polio in adult personnel at the National Institute for Virology (NIV), South Africa. METHODS: Polio neutralizing antibodies results on 776 NIV staff members tested between 1979 and 1999 and seroresponses in seronegative personnel given a booster vaccination were analysed. RESULTS: 613 of the 776 (79%) personnel had neutralizing polio antibodies to all three types, independent of age, gender, race or job category. Types 1 and 2 antibodies were found in 92% and 94%, respectively, but type 3 was less prevalent at 87%. Of the 93 persons seronegative to one or more types, 13 failed to respond to the first booster vaccination and 8 remained as non-responders after two booster vaccinations. Of the 19 personnel who were bled four days after booster vaccination, 16 (84%) had already developed an antibody response. CONCLUSIONS: Most (79%) adult laboratory personnel retained detectable levels of neutralizing antibodies to polio, independent of age, gender, race or job category, and even in those persons lacking detectable antibodies, most (84%) responded with a secondary immune response. Nevertheless the immunity gap, particularly to type 3, mandates routine screening of personnel potentially exposed to wild-type polio virus and a booster vaccination for seronegatives.

Adult↗
PubMed1998

A population-based seroprevalence study in South Africa as a tool in the polio eradication initiative.

A seroprevalence study for poliomyelitis was carried out on a sample of sera from a serum bank used for a vitamin A study. Vaccination coverage was satisfactory (80% or more) in five of nine provinces, although a prevalence of antibody to polio of 80% or more was found in all provinces. Serologic immunity (i.e., the prevalence of neutralizing antibodies) exceeded vaccination coverage, suggesting secondary spread of vaccine virus. However, whether or not water was supplied through a piped system was not associated with secondary spread of vaccine virus to nonvaccinated children. Seroprevalence studies are a valuable adjunct to acute flaccid paralysis surveillance, which is the standard surveillance instrument for the poliomyelitis eradication initiative. The use of available and suitable serum banks for seroprevalence investigations is a relatively cheap monitoring option that can yield very valuable information for the eradication initiative.

Age Distribution↗
PubMed1994

Surveillance of respiratory viruses. A 10-year laboratory-based study.

Respiratory virus isolates made at the National Institute for Virology from 1982 to 1991 were studied. An active virus surveillance programme, 'viral watch', which recruits throat swab specimens from a network of monitoring centres--mainly in the Witwatersrand and Vereeniging area with one centre in Middelburg--that represent a cross-section of the population, provided 68% of the specimens and 74% of the isolates, with an isolation rate of 25.5%. This was significantly higher than that of routine specimens (17.7%). Of the 966 isolates, influenza viruses accounted for 527 (54.7%), para-influenza for 122 (12.6%), respiratory syncytial virus for 34 (3.4%) and adenovirus for 106 (11.0%). Influenza viruses showed a definite seasonal peak between June and August whereas the other viruses, although they showed a winter predominance, were isolated throughout the year. An active virus surveillance programme is particularly valuable in monitoring respiratory virus epidemiology in the population.

Adenoviruses, Human↗
PubMed1993

Primary and secondary infection with human parvovirus B19 in pregnant women in South Africa.

A study of human parvovirus B19 infection in 1,967 pregnant women of all races in Johannesburg revealed an overall prevalence of 24.9% for IgG antibodies and 3.3% for IgM antibodies. Of the 64 IgM-positive sera indicating active infection, 62 were resistant to urea denaturation. No differences in the prevalence of IgG antibodies between population groups were observed, but active infections, as demonstrated by IgM antibodies, were significantly more prevalent in black than in white, coloured or Asian mothers.

Antibodies, Viral↗
PubMed1993

Hepatitis B virus prevalence in two institutions for the mentally handicapped.

A comparative study of the prevalence of hepatitis B virus infection in two institutions for the mentally handicapped was carried out between April and November 1989 and April and August 1991. The institutions were situated within 10 km of each other in north-eastern Johannesburg. One institution had a significantly higher prevalence of virus markers, 68% (139 of 203) compared with 23% (40 of 176), was in poorer condition and had more severely handicapped residents with more aggressive behaviour. However, the most important difference between the two institutions was that residents at the higher-prevalence institution were admitted at a considerably younger age. Younger individuals appear to be more susceptible to infection and are more likely to develop persistent infection, thus contributing to a greater pool of infection in the institution.

Adolescent↗
PubMed1993

Is antenatal screening for rubella and cytomegalovirus justified?

Altogether 2,250 asymptomatic pregnant women attending an antenatal clinic were investigated for serological evidence of past exposure to rubella and cytomegalovirus (CMV) as well as for active primary infection or reinfection/reactivation. Only 7 (0.3%) active rubella infections were diagnosed, none of them primary. Similarly, out of 132 patients with active CMV, only 5 primary infections (3.8%) were diagnosed; the vast majority--127 (96%)--had reactivation infections. No congenital rubella infections were detected, while the transplacental transmission rate for CMV was 6.4%. None of the infants followed up was clinically affected at birth or at 6 months. No racial differences in seroprevalences for CMV or rubella immunoglobulin were observed, but immunoglobulin antibody prevalence to CMV was significantly lower in the white group. From this study there appeared to be no indication for routine antenatal screening for CMV in asymptomatic mothers.

Carrier State↗
PubMed1992

Low antibody avidity in elderly chickenpox patients.

A small outbreak of chickenpox confirmed serologically in 3 elderly patients from a geriatric home is described. Disease was probably due to exogenous reinfection, yet nevertheless the avidity of specific antibodies measured by the urea denaturation test was even lower than in primary chickenpox controls, which themselves were, as expected, significantly lower than zoster controls. In elderly individuals susceptibility to reinfection with varicella-zoster virus (VZV) with clinical manifestation such as chickenpox may well be associated with the decay of specific humoral immunity detectable by antibodies of particularly low avidity, in contrast to reactivation of latent VZV presenting clinically as zoster, which is related to deficiencies in specific cellular immunity.

Aged↗
PubMed1991

Integration of hepatitis B vaccination into rural African primary health care programmes.

OBJECTIVE: To determine the efficacy of hepatitis B vaccine when added to the routine expanded programme on immunisation under field conditions in rural Africa. DESIGN: Infants were immunised according to two schedules--an early schedule at birth, 3 months, and 6 months and a later schedule to correspond with routine vaccination in the expanded programme on immunisation at 3 months, 4 1/2 months, and 6 months. SETTING: Venda, northern Transvaal, South Africa, a self governing region of 7460 square kilometers varying from rural villages to small towns. SUBJECTS: The 1989 birth cohort of Venda. MAIN OUTCOME MEASURES: Coverage for hepatitis B vaccine at first, second, and third doses; serological assessment of vaccine efficacy by prevalence of antibodies to hepatitis B surface antigen in infants who had completed the three dose course of immunisation; antibodies to hepatitis B core antigen to determine if natural infection occurred. RESULTS: Vaccine coverage for hepatitis B dropped sharply from 99% to 53% to 39% for the first, second, and third dose respectively. In contrast, vaccine coverage was maintained at 97-99% for the three doses of poliomyelitis vaccine. Serological evaluation of vaccine efficacy showed that only 3.5% of recipients of all three doses failed to develop antibodies to hepatitis B surface antigen. Only 6.6% of vaccine recipients were vaccinated according to either the early or later schedules whereas 93.4% received their doses of vaccine at intervals beyond the limits of either of the planned schedules. There was, however, no significant difference in seroconversion to the surface antigen between the "unscheduled" or scheduled groups of those who were vaccinated according to the early or late schedules. The pattern of prevalence of antibodies to hepatitis B core antigen, which showed a sharp fall in children aged over 7 months, suggested that the antibodies were acquired passively rather than by active infection. CONCLUSIONS: Supplementation of the present expanded programme on immunisation with hepatitis B vaccine in rural Africa is fraught with difficulties. However, the vaccine was effective within a fairly wide spacing of dosage. Adding hepatitis B vaccine to diphtheria, tetanus, and pertussis as a tetravalent vaccine is proposed as a means of effectively integrating it into the expanded programme on immunisation in Third World settings.

Developing Countries↗
PubMed1990

Susceptibility to poliomyelitis, measles, mumps and rubella in university students.

A serological study of 433 university students in various health care professions revealed levels of susceptibility of 2-7% for measles, 0-4% for mumps, 6-17% for poliomyelitis and a particularly disquieting 13-23% for rubella. Representing a developed population with a supposedly high level of immunisation cover these levels of susceptibility indicate students' vulnerability to outbreaks caused by viruses coming from reservoirs in under-immunised developing populations in the country. Nevertheless, no evidence of occupational exposure between the first- and final-year students was revealed. Immunisation efforts thus need to be urgently targeted not only to developing but also to developed populations in South Africa.

Adolescent↗
PubMed1990

Measles, mumps and rubella immunization at nine months in a developing country.

The antibody responses and reactogenicity of a measles, mumps and rubella vaccine in 9-month-old and 15-month-old black children in South Africa were compared. The antibody response to the measles component was marginally better in the older group, but no differences were observed in the response to the mumps and rubella components. Reactogenicity was similar in the two age groups. Therefore it is possible that a trivalent measles, mumps and rubella vaccine can safely and effectively replace routine measles immunization at 9 months of age in this population. Whether routine immunization policy should incorporate such a vaccine depends on the extent of acceptance of measles vaccination. In urban populations of developing countries with high rates of measles immunization, routine vaccination at 9 months might interrupt circulating wild type rubella and provide sufficient herd immunity to protect susceptible women of childbearing age. It also should decrease significantly the complications associated with wild type mumps infection. The replacement of measles vaccine by a trivalent vaccine may be very cost-effective.

Black or African American↗
PubMed1986

Laboratory studies of the 1984 influenza epidemic on the Witwatersrand.

A particularly severe outbreak of influenza occurred on the Witwatersrand from May to August 1984, caused sequentially by influenza A (H3N2), B/influenza and influenza A (H1N1) viruses. Although the precise extent of the infection was impossible to determine, valuable anecdotal information was provided by a network of sentinel sampling stations in private practices, clinics and hospitals, representing a cross-section of population groups on the Witwatersrand. This active surveillance programme was invaluable in providing some 85% of all the specimens, the remainder being routine clinical specimens; in addition, isolation was approximately twice as efficient for the actively acquired specimens than for the routine ones. The epidemic affected all individuals approximately equally, regardless of age, race or socio-economic status. Infection with H1N1 virus tended to predominate in the younger age group, 78% of isolates being from subjects under 30 years of age, whereas 71% of H3N2 isolates came from subjects over 30 years of age. The B/influenza isolates tended to be more evenly dispersed. Novel strains of B/influenza and H1N1 viruses were introduced into the country and possibly contributed to the greater than usual severity of the epidemic. An active surveillance programme is essential to monitor the extent of influenza virus activity and to alert virologists to the introduction of new strains, although at present forecasting of future influenza epidemics is not possible with any significant degree of reliability.

Black or African American↗
PubMed1986

Tetanus antibodies as a marker of potential efficacy of killed polio immunization.

The use of antibodies to tetanus toxin as a marker of efficacy of parenteral immunization was examined in a randomized sample of 1212 sera representative of the total black infant population of the RSA between 24 and 35 months. All but one of these sera had protective levels of antibodies measured by enzyme-linked immunosorbent assay. In contrast, in a previous study only 59-80% had tritypic immunity to polio and 70-84% mono- or bitypic immunity. Thus, this serological marker was found to be unreliable and some possibilities for this remarkably high level of antitetanus antibodies are considered.

Black or African American↗
PubMed1986

A comprehensive investigation of immunity to poliomyelitis in a developing country.

A comprehensive nationwide surveillance program of serologic immunity of two-year-old black children, combined with evaluation of vaccine quality and distribution, was carried out in South Africa during 1983-1984. Sera were randomly collected from urban and rural groups and cluster samples collected from the semi-urban group. The sample represented 0.23% of the total target population. Satisfactory levels of immunity were found in the urban (80%) and semi-urban (71%) groups but a disquietingly low level was found for the rural group (59%). Individual districts in the rural group could be singled out for directed cluster sampling at a later stage. History and documentation of immunization corresponded well to serologic findings and revealed also a fairly substantial level of natural immunization among individuals who, on history, had received no vaccine. Some 95% of random samples of vaccine recalled from the field showed satisfactory levels of potency. An immunity surveillance program such as this is ideally suited and highly cost-effective for developing countries with incomplete immunization to prevent large-scale buildup of immunity deficit. The technique, however, is too insensitive to detect localized community immunity defects.

Antibodies, Viral↗