Relationship between tuberculin reactivity and hepatitis B virus infection in the Northwest Territories.

Of 370 NWT Inuit or Dene who were HBsAg-positive, only 31 had HBeAg. Persons who were PPD negative were 6.2 times more likely to be HBeAg-positive than those who were PPD positive, but this inverse association applied only to those 30 years of age. We further analyzed a group of 3,378 Inuit whose status was known for HBV serologic markers and PPD reactivity. Overall, a significantly greater proportion (76.2%) of HBsAg positives were PPD reactive in comparison to those positive for anti-HBs (67.2%) or who had no HBV markers (43.2%). For persons 30 years of age who were positive for HBsAg or anti-HBs there was no significant difference between the proportions with PPD reactivity but a significantly smaller proportion of PPD reactivity was found in the no marker group. Among persons 30 years of age, the proportions of those who were PPD reactive were statistically equivalent across all three HBV marker groups. We conclude that patterns of HBV infection in NWT are random with respect to tuberculin reactivity resulting from either exposure to M. tuberculosis or administration of BCG vaccine.

Success of a program of routine prenatal screening for hepatitis B surface antigen: the first 2 years.

Prenatal screening for hepatitis B surface antigen (HBsAg) restricted to women with defined risk factors for chronic hepatitis B virus (HBV) infection fails to identify many carriers. A centralized program of routine HBsAg screening for all pregnant women in Alberta was introduced in 1985. We collected and analysed data for the first 2 years of the program in Edmonton to determine the frequency of risk factors for HBsAg positivity, the proportion of multiparous HBsAg-positive women not identified in previous pregnancies, the efficiency and cost-effectiveness of providing immunoprophylaxis to infants at risk of HBV infection and the degree of success in inducing adequate protection. A total of 149 women (158 pregnancies) were found to be HBsAg positive. Risk factors were readily ascertainable for 85% of the women; the remaining 15% would not have been identified through risk-selective screening. The most common risk factors were Oriental ethnic origin, history of hepatitis, jaundice or multiple transfusions of blood or blood products, and occupational exposure to blood. Although 86% of the multiparous HBsAg-positive women had risk factors, only 7% had been identified in previous pregnancies. The Alberta program appears to be cost-effective. We conclude that only routine prenatal screening will identify all infants at risk of perinatal HBV infection and that a comprehensive public health program involving central laboratories, private physicians and public health staff can be highly effective and efficient in protecting infants against hepatitis B.

Comparative seroepidemiology of cytomegalovirus infection in the Canadian Arctic and an urban center.

We conducted a seroepidemiologic study of cytomegalovirus (CMV) infection among 9,928 Inuit (Eskimo), Dene (Indian) and non-native inhabitants of the Northwest Territories (NWT) of Canada between April 1983 and March 1985. 4,184 inhabitants of Edmonton, a large predominantly white urban center served as controls. Sera were screened for antibody to CMV by enzyme-linked immunosorbent assay (ELISA). The prevalence rates of CMV antibody increased with age in all ethnic groups. By the age of two years 69.2 percent of Dene, 63.5 percent of Inuit, 33.3 percent of non-native and 22.9 percent of Edmonton children had CMV antibody. Over the age of five years Inuit children had higher rates of CMV antibody than Dene children (P less than .05) reflecting differences in infant adoption, breastfeeding practices and patterns of child care in the two native groups. By the age of 15 to 19 years 81.1 percent of Dene and 88.5 percent of Inuit women had CMV antibody compared to 48.8 percent of non-native and 50.9 percent of Edmonton women (P less than .05). Native children had higher prevalence rates than non-native children living in the NWT (P less than .05). Compared to similarly aged Edmonton residents, non-native children in the NWT 2 to 4 years and 5 to 9 years of age had a higher prevalence of CMV antibody (P less than .05). We observed a higher prevalence rate of CMV antibody among non-native children (10-14 years) and young women (15-19 years) living in predominantly native communities compared to those living in predominantly non-native communities in the NWT (P less than .05).(ABSTRACT TRUNCATED AT 250 WORDS)

Extension of the epidemiology of hepatitis B in circumpolar regions through a comprehensive serologic study in the Northwest Territories of Canada.

We conducted a seroepidemiologic study of hepatitis B virus (HBV) infection among 14,198 Inuit (Eskimo), Dene (Indian), and non-native inhabitants of the Northwest Territories (NWT, total 1982 population 47,053) between April 1983 and March 1985. Participants represented almost all of the NWT communities and included approximately half of the total indigenous population. Sera were screened for hepatitis B surface antigen (HBsAg) and antibody to hepatitis B surface antigen (anti-HBs) by radioimmunoassay. A total of 428 persons (3.0%) were positive for HBsAg; their mean age was 41.5 years and 68.7% were greater than 30 years old. Anti-HBs was detected concomitantly in 153 (35.7%) of these persons and present as a single marker in 2,943 sera (20.7%). Overall prevalence rates for HBsAg were marginally higher among Inuit than Dene (3.9% and 2.9%, respectively; P less than 0.05), as were rates for anti-HBs (24.5% and 21.5%, respectively; P less than 0.01). Marker rates among the 2,776 participants of other ethnic groups, predominantly whites, were distinctly lower (HBsAg 0.3%, anti-HBs 8.5%) than among Inuit or Dene populations (P less than 0.01). The prevalence of HBsAg and anti-HBs increased with each decade of life in all five geographic regions, but there were marked differences among the regions as well as among communities within regions. The greatest concentration of HBV markers was in the Baffin Region (36.0% positive for HBsAg or anti-HBs). Hepatitis B e antigen (HBeAg) was detected in only 37 of 421 persons (8.8%) positive for HBsAg; most were less than or equal to 20 years old and were clustered in a few communities with the highest HBV marker rates.

Failed rubella immunization in adults: association with immunologic and virological abnormalities.

Immunologic and virological studies were performed in 13 adults (12 women and one man) who failed to seroconvert (as shown by rubella hemagglutination-inhibition [HAI] techniques) after single or repeated courses of HPV-77 DE/5 or RA 27/3 rubella virus vaccine. Immunologic sensitization to rubella virus was assessed from six months to eight years (mean, 3.0 years) after the last course of rubella virus vaccine by using HAI, enzyme-linked immunosorbent assay (ELISA), single radial hemolysis (SRH), neutralization, and virus-specific lymphoproliferative techniques. Despite HAI seronegativity, 11 of 13 subjects demonstrated significant sensitization to rubella virus proteins, as indicated by ELISA (10 of 13), neutralization (9 of 11), SRH (4 of 11), and rubella lymphocyte stimulation techniques (9 of 13). In addition, rubella virus was isolated from three individuals by using cocultivation techniques with peripheral blood mononuclear cells. Failed rubella immunization in adults may have more significance than previously recognized in view of altered patterns of virus-specific immunity and the association of this failure with the rubella virus carrier state.

Hepatitis B and the dental profession: response to hepatitis B vaccine in Canadian dental personnel. A study by the Canadian Red Cross Collaborative Group.

Reports from North America and Western Europe based on the prevalence of hepatitis B virus markers and frequency of hepatitis B in dentists indicate that this professional group is at increased risk of HBV infection. We gave hepatitis B vaccine (Merck Sharp and Dohme) to 251 dental students and faculty/staff members at faculties of dentistry in three Canadian universities. Participants received three 20 micrograms doses of vaccine, at 0, 1 and 5.5 months. Anti-HBs was detected in 42.9 per cent of persons after the first dose of vaccine, in 96.8 per cent after the second dose and in 99.6 per cent after the third dose. A follow-up of 150 persons 22 months after the first dose of vaccine indicated that high or medium levels of anti-HBs were maintained in nearly 87 per cent of the participants and only six per cent had no detectable antibody. Female vaccinees in each age group developed anti-HBs more promptly, and more of them were in the high antibody-response range in comparison to male participants. There were no unacceptable reactions to the vaccine. Our favourable experience with this vaccine would support recommendations for its routine use among dental professionals in Canada and other countries where this group is at increased risk of HBV infection.

Impact of measles in Canada.

The reported incidence of measles in Canada in 1981 was reduced 97% from the average annual rates during the prevaccine period, 1949-1958. Throughout recent years the age-specific incidence of reported cases of measles has remained highest in the group five to nine years of age, but there has been a definite increase in the proportion of cases of measles in persons greater than 10 years of age. During the extensive measles epidemic in Alberta in 1979, a high proportion of the reported cases occurred in adolescents and young adults previously vaccinated with killed vaccine, and the majority of these developed atypical measles syndrome. In Canada, from five to 36 patients per 100,000 population have required hospitalization annually for complications due to measles over the past 16 years. Measles-related deaths have declined in a pattern similar to that for reported incidence. Despite favorable trends in the control of measles in Canada, the social and economic impacts of this disease remain substantial and warrant a nationwide effort to eliminate indigenous infection.

Prospective immunological assessment of arthritis induced by rubella vaccine.

A prospective study was carried out to correlate the development of joint symptoms after rubella immunization with pre- and post-immunization rubella-specific immunological responses. Arthralgia or arthritis or both occurred in 10 of 37 adult female volunteers at a mean time of 17.0 days after immunization with the RA 27/3 rubella vaccine. All individuals studied before immunization were seronegative for rubella by either the hemagglutination inhibition or the single radial hemolysis technique. In contrast, rubella enzyme-linked immunosorbent assay or lymphoproliferative responses or both were positive in 27 of 37 (73%) individuals tested before receiving the vaccine. Rubella enzyme-linked immuno-sorbent assays carried out before immunization were positive at high levels (mean E = 0.536) in four individuals who developed recurrent episodes of arthritis after administration of the vaccine while remaining at low levels preimmunization in subjects who developed transient arthralgia (E = 0.238) or no joint manifestations at all (E = 0.288). These data provide preliminary evidence suggesting that rubella vaccine-associated arthritis may occur as a consequence of secondary, rather than primary, infection with rubella virus and that the presence of circulating, nonneutralizing rubella antibody may enhance the development or severity (or both) of the associated postinfection joint manifestations. Assessment of rubella hemagglutination inhibition, hemagglutination inhibition (immunoglobulin M), and enzyme-linked immunosorbent assay serological responses at 6 weeks and 6 months post-immunization revealed no significant differences between patients who developed and those who did not develop joint manifestations. Rubella lymphoproliferative responses were elevated at 6 weeks post-immunization in the group developing arthralgia or arthritis or both, with no difference between the groups observed at 6 months post-immunization.

Haemolytic uraemic syndrome: evidence of multiple viral infections in a cluster of ten cases.

During July 1979, ten patients were admitted to the hospital with bloody diarrhoea followed by manifestations of haemolytic uraemic syndrome (HUS): acute microangiopathic haemolytic anaemia, intravascular coagulopathy, and impaired renal function. Ages ranged from 13 months to 58 yr, with only two patients more than 5 yr old. In a household that included seven children born to three sisters who married three brothers, six children required hospitalization for bloody diarrhoea and four developed HUS; the father of one case and the maternal grandmother also developed bloody diarrhoea. Echovirus type 11 was isolated from the pharyngeal secretions or faeces of all members of the household with bloody diarrhoea, with the exception of the grandmother. Picornavirus-like particles were seen by direct electron microscopy (E/M) in faeces from four other HUS patients and an adenovirus in one, but these viruses failed to replicate in cell cultures. Parvovirus-like particles were seen by E/M in faeces from six patients. Serological examination indicated recent infection with one or more enteroviruses (echovirus 11, coxsackieviruses A4, B2, B4) in nine cases. Combined viral studies revealed presumptive evidence of recent infection with two or more viruses in all of the patients with HUS. Stools were negative for bacterial pathogens including campylobacter, salmonella, shigella, and yersinia organisms. Only one of nine patients tested had circulating immune complexes. Our data support the concept that the pathology seen in HUS may be due to a Shwartzman-type reaction provoked by concurrent infection with two or more viral agents.

The outcome in children with congenital cytomegalovirus infection. A longitudinal follow-up study.

Infants with congenital cytomegalovirus (CMV) infection were identified through urine cultures of 15,212 consecutive neonates and studied prospectively to determine whether their neurodevelopmental and audiologic status was different from that of matched uninfected control subjects. Of 64 children with congenital CMV infection, three died, 11 could not be located for follow-up, one had quadriplegic cerebral palsy, and seven had varying degrees of sensorineural hearing loss. All matched control subjects were normal neurologically, and none of them had sensorineural hearing impairment. The Stanford-Binet test revealed scores within the normal range, at 3 and 5 years of age, for both children with CMV infection and matched control subjects, as did the preschool assessment (Wide Range Achievement Test) in children older than 5 years. However, in children with CMV infection, the home environment was less stimulating, discipline and punishment were more readily implemented, and behavioral problems were significantly greater than in the matched control subjects.

Congenital cytomegalovirus infection in an urban Canadian community.

congenital cytomegalovirus (CMV) infection was diagnosed in 64 (0.42%) of 15,212 infants born in Hamilton, Ontario, Canada, during a period of 44 consecutive months. Urine specimens collected within 48 hr of birth were screened for CMV by inoculation into cell cultures. Only four infants had clinical or laboratory findings in the first week of life that suggested cytomegalic inclusion disease; CMV infection was mild or inapparent in the remainder. Fourteen CMV-positive infants (21.9%) had birth weights of less than or equal to 2,500 g, including eight of 11 premature infants (less than or equal to 37 weeks of gestation). Only five CMV-positive infants were small for gestational age. Overall, there were no significant differences between CMV-positive and CMV-negative infants in mean gestational age or mean measurements of weight and head circumference at birth. Mothers of CMV-positive infants were predominantly younger, primiparous women of lower educational and economic status, and the number who were unmarried was about threefold greater than among mothers of uninfected infants.

Comparison of responses to influenza A/New Jersey/76-A/Victoria/75 virus vaccine administered intradermally or subcutaneously to adults with chronic respiratory disease.

Serum HAI (hemagglutination inhibition) antibody responses were compared in two groups of 70 age-matched patients (age range, 17 to 82 years) who were vaccinated with bivalent influenza A/New Jersey/76-A/Victoria/75 whole-virus vaccine. The group that was vaccinated intradermally received 40 chick cell-agglutinating units of each viral antigen in 0.1 ml, and the group that was vaccinated subcutaneously received 200 chick cell-agglutinating units of each antigen in 0.5 ml. The serum HAI antibody response to A/New Jersey/76 antigen was significantly higher in the group that was vaccinated subcutaneously; this difference was particularly evident in patients less than or equal to 50 years old. The serologic response to A/Victoria/75 antigen did not differ significantly between the two groups. Levels of antibody before vaccination indicated previous widespread exposure of patients to influenza A/Victoria/75 virus, but not to influenza A/New Jersey/76 virus. Such differences in prior immunologic experience with a particular strain of influenza virus probably determine whether the intradermal route of vaccination is as effective as, or inferior to, the subcutaneous route.