Epidemiology of Dictyocaulus viviparus in Louisiana (U.S.A.)

An epidemiological investigation was conducted during a 1-year period on a permanent pasture naturally contaminated with Dictyocaulus viviparus and grazed by a varying number of yearling cattle. Seasonal variation in pasture infectivity to cattle was monitored by monthly slaughter of tracer calves, slaughter of pairs of resident yearlings at 30-60-day intervals, herbage larval recovery and by counts of first stage larvae in feces (modified Baermann technique) of resident cattle. A clinical outbreak of dictyocauliasis occurred during January-March 1986 and was associated with peak levels of pasture infectivity. Carrier animals were considered responsible for the survival of infection over summer. Although soil samples were taken regularly on a monthly basis to study the epidemiological importance of the soil as a source of infection, infective larvae were not recovered at any time. The epidemiological pattern observed in the present study provides basic information on the factors involved in infection and diseases outbreaks under sub-tropical conditions.

Prevention of group B streptococci transmission during delivery by vaginal application of chlorhexidine gel

In a prospective study in 227 parturients, carriership of group B streptococci was established to be 25%. In carriers, transmission of streptococci to the newborn occurred in 50%. 10 ml of a chlorhexidine gel containing hydroxypropylmethylcellulose was introduced into the vagina during labor in 17 parturients, who were known to be carriers of group B streptococci from the first trimester of pregnancy. In none of the newborns from these mothers colonization by group B streptococci did occur. Vaginal application of chlorhexidine may prevent transmission of group B streptococci, and serve as an alternative to intrapartum prophylaxis using antibiotics. A large multicenter randomized controlled study should be performed to confirm this hypothesis.

Prevention of vertical transmission of hepatitis B virus by yeast recombinant hepatitis B vaccine

In order to prevent vertical transmission of hepatitis B virus (HBV), yeast recombinant HB vaccine at a dose of either 5 mcg or 10 mcg was administered to 185 infants born to mothers who were positive for HBs antigen (HBsAg). All of them developed antibody to HBsAg (anti-HBs) after three vaccinations. Generally, the cut-off index (COI) of anti-HBs by radioimmunoassay (RIA) was higher in the 10 mcg dosage group than in the 5 mcg dosage group. The geometric mean titer (GMT) of anti-HBs, as measured by quantitative RIA, in the former group was 2.4 times that in the latter one month after the third vaccination. The incidence of clinical reactions was only 4% in a total of 561 injections, and none of the reactions were severe. It is concluded that recombinant HB vaccine is safe and has excellent immunogenicity for infants requiring prevention of HBV vertical transmission. It is also suggested that 10 mcg doses of the recombinant HB vaccine can provide more solid protection to high-risk infants without serious adverse reactions.

The effects of hepatitis B vaccination on infants born to carriers without HBe antigenemia

A retrospective study on fifty-three patients born to hepatitis B surface antigen (HBs antigen) positive mothers was carried out. Among 17 patients born to hepatitis B e antigen (HBe antigen) negative mothers, six patients received hepatitis B(HB) vaccination and eleven did not. None of the six patients who had received HB vaccination showed seroconversion, while six of the 11 patients (54.5%) without HB vaccination did show seroconversion. There was no definite correlation between the frequency of seroconversion and the administration of HB immune globulin (HBIG). HB vaccination alone may be sufficient to protect infants born to HBe antigen negative mothers from HB viral infection.

[Hygiene problems with ornamental birds in the household]

Approximately 8 million pet birds are kept in the Federal Republic of Germany. The number of households where these birds are living is insignificantly lower, and the birds are usually kept as singles. Hygienic problems can arise due to the close contact between humans and birds. In view of the different pet birds species originating from different biotopes, specific knowledge is often lacking regarding adequate housing, nutrition and general management. This can result in a decrease of natural resistance and therefore can lead to diseases of those birds. Therapy, performed by a nonveterinarian, usually does not only affect the birds, but also endangers the owners themselves. Especially, the carrier state of newly purchased birds with pathogens hazardous for human health has to be considered. Psittacosis has to be mentioned as one of the major zooanthroponoses deriving from birds. This requires to reconsider governmental measures to cope with this disease including policies of bird import as one of the major reasons for spreading the disease. Better management conditions can extend the life expectation of birds. This might also lower the fluctuation within the pet bird population and therefore biohazards for humans. Therefore, instruction and advice of pet bird-owners are necessary.

Characteristics of HBsAg subtypes distribution in Beijing area

This paper reports that 300 HBsAg positives were distributed in 262 families. 14 of the 262 families had two or more HBsAg positives. In the 14 families, 7 showed the same subtype HBsAg, probably due to HBV infection from family source. Another 7 families showed HBsAg of different subtypes, definitely due to infections from the community.

Prevention of hepatitis B virus carrier state in infants according to maternal serum levels of HBV DNA

235 infants of HBeAg-carrier mothers in Hong Kong were assigned to four study groups. Groups I, II, and III received hepatitis-B (HB) vaccine at birth and at 1, 2, and 6 months. Group I also received seven monthly injections of HB immunoglobulin (HBIg), and group II received one HBIg injection at birth. Group III received vaccine only and group IV received placebo for both vaccine and HBIg. At the age of 3 years, all infants of the three treatment groups were significantly protected against the HB virus (HBV) carrier state compared with the placebo group (p less than 0.0001); the protective efficacy rates in groups I, II, and III were 87%, 80%, and 65%, respectively. At all times, group I was significantly better protected than group III. In groups III and IV, infants of mothers with serum HBV DNA levels of 5 pg/ml or above were at a significantly higher risk of acquiring the HBV carrier state than those whose mothers had HBV DNA levels below 5 pg/ml. This difference was not significant in groups given HBIg. Of the 183 infants who initially escaped HBV infection, 73 (40%) had transient and 8 (4%) chronic HBV infection between 6 and 36 months. Vaccinated infants who had actively formed anti-HBs remained well protected against the HBV carrier state. However, infants in groups I and II with no active anti-HBs response to vaccine became at risk for the HBV carrier state when the passively acquired anti-HBs antibodies had disappeared. HBIg should be included in HB vaccination schedules for all infants of HBeAg-positive mothers.

The carrier state: methicillin-resistant Staphylococcus aureus. A hospital study "screening of hospital personnel" for nasal carriage of Staph aureus

Methicillin resistant Staph Aureus (MRSA) were studied in a 300 bedded Central Government Hospital Rawalpindi, in which 291 staff members were screened by nasal swabbing. Of 125 cases carrying staph aureus 5 (1.78%) were methicillin resistant. They were treated with Bacitracin ointment to be applied to interior nares four times a day for one week. Hexachlorophane baths daily, chlorhexidine shampoo once daily for a week, and were taken off duty from wards for one day.

Hepatitis B infections after gynaecological surgery

When acute hepatitis B developed in 3 patients who had had gynaecological surgery, the surgeon was found to be a carrier of hepatitis B e antigen. Of 268 patients operated on by this surgeon in one hospital, 247 were screened for markers of recent or current hepatitis B. 22 (9%) had such markers, associated with symptoms in 5. The operations carrying greatest risk of infection were hysterectomy (10/42) and caesarean section (10/51). These findings strengthen the case for vaccination of all surgeons and medical students against hepatitis B.

Protective efficacy of plasma-derived hepatitis beta vaccine in preventing perinatal transmission of HBV infection in infants of HBsAg/HBeAg positive mothers

Two hundred and four newborn infants of HBsAg/HBeAg carrier mothers were randomly assigned into three groups. Group A (69 infants) received full-dose HB vaccine, group B (70 infants) received half-dose HB vaccine at birth, 1 month, 3 months and group C (65 infants) were untreated control group. After twelve months follow-up the cumulative incidence of HBs antigenemia was 17.2%, 30% in group A, B respectively as compared with 78.4% in group C (p less than 0.001). The protective efficacy rates (PER) of group A and B were 78.1% and 61.7% respectively (p less than 0.05). The vaccine was also effective in preventing persistent HBsAg carriers (HBsAg positive for at least 6 months). The PER of group A and B were at least 74.9% and 49.2% respectively (p less than 0.001) at 1 year follow-up. From the practical point of view and economic reasons administration of full-dose HB vaccine give better protection to high risk infants.

Subclinical human papillomavirus infections in male sexual partners of female carriers

The male sexual partners of 156 women with human papillomavirus infection of the cervix uteri were examined. In 120 men (77 per cent) penile lesions were found on examination of the penis via a colposcope (peniscopy) the most common of which were flat acetowhite lesions (53 per cent). Predilection sites of lesions were the urethral meatus and the corona glandis (23 and 19 per cent of the lesions, respectively). Using filter in situ hybridization human papillomavirus-deoxyribonucleic acid was found in penile smears of 61 men (39 per cent). The cancer-associated viral types (human papillomavirus 16 and 18) were identified in 75 per cent of the human papillomavirus positive men. Viral types of sexual partners were identical in 87 per cent. The correlation between infections with human papillomavirus 16 and 18, and the severity of the cervical lesion was significant in corresponding sexual partners. Our results support the hypothesis that male sexual partners represent a risk factor by acting as a reservoir for genital infections with papillomaviruses. The majority of human papillomavirus infections are of subclinical character. They require sensitive diagnostic techniques, such as peniscopy and hybridization for their identification. Detection and treatment of subclinical human papillomavirus infection in men may be important for the prevention of genital cancer in women.

The significance of wild birds (Larus sp.) in the epidemiology of Campylobacter infections in humans

During much of the present century, the population of herring gulls in Britain has increased rapidly (Cramp, Bourne & Saunders, 1973; Chabrzyk & Coulson, 1976; Monaghan & Coulson, 1977). Accompanying this changes was an increased utilization by these birds of human waste as a food supply, particularly sewage and refuse emanating from our towns and cities (Monaghan, 1983; Hortonet al.1983). This, coupled with their habits of roosting on agricultural land and water storage reservoirs and of breeding on inhabited buildings, has given rise to concern over the role of these birds in the spread of disease to man and domestic animals (e.g. Fenlon, 1981; Reillyet al.1981; Butterfieldet al.1983; Monaghanet al.1985; Girdwoodet al.1986).

[Everyday contact spread of viral hepatitis B]

The results obtained in the study of the characteristic features of the spread of viral hepatitis B under the conditions of family foci are presented. Children with viral hepatitis B have been found to infect 4-5 persons per 1,000 contacts, while adults infect not more than 1 person per 1,000 contacts. The results of the study have led to the conclusion that the idea of the potential danger of hepatitis B patients as the source of infection depends on the forms of the infectious process taken into account in evaluating its epidemiological significance. Latent cases of hepatitis B virus infection appear more frequently among the contacts of sick children than among those of sick adults, but the manifest forms of the disease are more frequently caused by infection contacted from sick adults.

Factors determining the development of hepatocellular carcinoma in hepatitis B surface antigen carriers. A comparison between families with clusters and solitary cases

This article documents five families with clusters of hepatocellular carcinoma (HCC), including one in which three successive generations were involved. All the 12 patients in these five families and 96.3% of the patients in 54 families with solitary cases of HCC seen during the same period were hepatitis B surface antigen (HBsAg)-positive. The prevalence of HBsAg in families with clusters and solitary cases of HCC was compared. The clustering of HCC in the five families reported could not be accounted for by a higher HBsAg carrier rate or an earlier age of onset of the hepatitis B virus infection. An attempt was made to identify the factors that determine the development of HCC in HBsAg carriers.

Significance of maternal and infant serum antibodies to hepatitis B core antigen in hepatitis B virus infection of infancy

The significance of IgM and IgG class antibodies to hepatitis B virus (HBV) core component (anti-HBc) was investigated in a study of maternal-fetal HBV transmission. An IgM anti-HBc response was lacking in the majority (49/53) of HBV-infected infants. This antibody thus cannot be used as an indicator of transplacental infection. However, most infants who became HBsAg positive during the first 6 months of life acquire infection in the perinatal period rather than transplacentally. Passively transferred maternal IgG anti-HBc in the infant and additional IgM anti-HBc positively in the carrier mother have no modulating influence on HBV infection of infants born to HBV carrier women.

[Characteristics of the formation of the HBsAg carrier state among pregnant women and newborn infants and their role in the spread of hepatitis B]

The authors analyze the incidence rate of HBsAg carriership among 8, 120 pregnant women and 261 newborn infants at different periods after birth. The levels of HBsAg carriership among pregnant women and the members of their families, as well as among the personnel of maternity clinics and blood donors, have been established. The rate and time of the detection of HBsAg in infants born to mothers found to be HBsAg carriers have been determined. Measures for the prophylaxis of hepatitis B are discussed with due regard to the specific epidemiological features of the spread of HBsAg carriership, established in this study, and to the presence of antibodies to HBsAg among the above-mentioned groups of the population.