Vitamin A supplementation and increased prevalence of childhood diarrhoea and acute respiratory infections.

There is uncertainty over whether vitamin A supplementation reduces morbidity among children with subclinical deficiency of the vitamin. Hence a double-blind, placebo-controlled trial of the effect of vitamin A supplementation on childhood morbidity was conducted among 11,124 children aged 6-83 months in the northwest of Haiti. After a random start, children were sequentially assigned by household units to receive either megadose vitamin A or placebo in three distribution cycles 4 months apart. 2 to 8 weeks after each administration of the vitamin A and placebo capsules, indicators of childhood morbidity were reassessed through interviews conducted in the homes of participating families. The vitamin A group was found to have an increased 2-week prevalence of all symptoms and signs of childhood morbidity assessed, including diarrhoea (rate ratio [RR] = 1.09, 95% confidence interval 1.05-1.14), rhinitis (RR = 1.02, 95% confidence interval 1.00-1.04), cold/flu symptoms (RR = 1.04, 95% confidence interval 1.01-1.06), cough (RR = 1.07, 95% confidence interval 1.03-1.11), and rapid breathing (RR = 1.18, 95% confidence interval 1.09-1.27). The study shows an increased 2-week prevalence of diarrhoea and the symptoms of respiratory infections after vitamin A supplementation.

PIP: In the late 1980s, 11,124 children 6-83 months old, living in the sparsely populated northwest of Haiti participated in a double-blind, placebo-controlled trial of the effect of vitamin A supplementation on child morbidity. An ophthalmic assistant and a supervising ophthalmologist examined all children 2 years old. 30 children had vitamin A deficient related corneal disease (20 with corneal xerosis and 10 with corneal ulceration, keratomalacia, and/or corneal scarring). The children received either a capsule containing 200,000 IU of vitamin A and 40.6 mg vitamin E or a capsule containing only 40.6 mg vitamin E (placebo) every 4 months. Field workers interviewed caretakers 2-8 weeks after the children received their capsules to gather data on signs and symptoms of illness. Children in the vitamin A group were more likely to have a higher prevalence of diarrhea and of respiratory infections than the placebo group (e.g., 1st cycle, 42 vs. 36% for diarrhea and 18 vs. 15% for rapid breathing, rate ratios = 1.6 and 1.19, respectively). The risk of morbidity was highest 8-17 weeks after receiving the megadose of vitamin A. These findings indicate that prevalence of diarrhea and respiratory infections increased 2 weeks after vitamin A supplementation. Mortality rates of the 2 groups were essentially the same. The mortality rate of nonparticipants was higher than that of participants (52/1000 vs. 23/1000), however, suggesting that the supplements may have had some benefit.

Antibodies to arboviruses in an Alaskan population at occupational risk of infection.

A total of 435 United States Geological Survey and United States Forest Service workers in Alaska were studied for serologic evidence of past infections with four arboviruses known or suspected to be human pathogens. Of the personnel tested, 36 (8.3%) had the neutralizing antibody to Jamestown Canyon but not snowshoe hare virus, 6 (1.4%) had the antibody to snowshoe hare but not Jamestown Canyon virus, 53 (12.2%) had the antibody to both viruses, 17 (3.9%) had the antibody to Northway virus, and 15 (3.4%) had the antibody to Klamath virus. The indices most significantly correlated with presence of the Jamestown Canyon and snowshoe hare antibodies were the amount of fieldwork (p less than 0.001 for both antibodies) and the duration of employment by the agencies (p less than 0.0001 for Jamestown Canyon and 0.004 for snowshoe hare). The antibody to the four arboviruses also correlated strongly with a history of travel in certain remote or wilderness areas in Alaska (p values ranged from less than 0.001 to 0.086).

Epidemiology of cytomegaloviral infections: recommendations for prevention and control.

Cytomegalovirus (CMV) causes serious illness in immunocompromised patients and congenitally infected neonates. Knowledge of the epidemiologic characteristics of CMV remains limited, but specific and practical measures can help prevent the transmission of infection to persons in high-risk groups. Good personal hygiene, especially hand washing, is the most effective means of preventing the acquisition of CMV by pregnant women and by individuals who care for children and immunocompromised patients. Screening programs for the identification of seronegative pregnant women and female hospital employees or of asymptomatic children who are excreting CMV are not practical or beneficial; educational programs are recommended instead. Since CMV infection is endemic in the community, exclusion of known CMV excretors from schools is not indicated. Exposure of premature infants or of organ transplant recipients and other severely immunocompromised patients to exogenous sources of CMV, such as blood transfusions, should be minimized. These recommendations may need to be revised in the future as more specific knowledge of the epidemiology of CMV is gained.

The syndrome of unexplained generalized lymphadenopathy in young men in New York City. Is it related to the acquired immune deficiency syndrome?

To establish whether the syndrome of unexplained generalized lymphadenopathy in homosexual men was new and related epidemiologically to the acquired immune deficiency syndrome (AIDS), we reviewed 3,139 pathology reports of lymph node biopsies performed at seven hospitals in New York City during the years 1977 through 1981. Three hundred twenty-nine patients (10%) were categorized as having unexplained lymph node hyperplasia; a detailed medical record review of 30% of these patients revealed three, two, six, eight, and 16 cases of unexplained generalized lymphadenopathy in the five years studied, respectively. Of these 35 cases, 26 (74%) occurred in males aged 16 to 44. A record review of 68 additional male patients aged 16 to 44 years with unexplained lymph node hyperplasia in two of the hospitals showed a similar increase in cases of unexplained generalized lymphadenopathy during the five-year period. Twenty-one of 25 cases in males with known sexual orientation were homosexual or bisexual. The increase in the syndrome of unexplained generalized lymphadenopathy from 1978 to 1981 and the characteristics of the population affected are similar to those observed for AIDS.

Antibody to Ebola virus in guinea pigs: Tandala, Zaire.

A case-control study was conducted to investigate the findings of antibody to Ebola virus in the serum of a guinea pig from Tandala, Zaire. Case households, defined by the possession of one or more guinea pigs, were compared to neighboring households without guinea pigs. Seven (5.1%) of 138 samples of human sera and 36 (26%) of 138 samples of guinea pig sera had antibody to Ebola virus. There was no clustering of seropositivity among humans or guinea pigs within households, nor was there any association between the ownership of guinea pigs and seropositivity among household members. These data suggest sporadic subclinical infection of guinea pigs and humans without a dominant role for person-to-person or guinea pig-to-guinea pig transmission.