Tag: risk factors

Alleged link between hepatitis B vaccine and chronic fatigue syndrome

In 1989, 3456 cases of hepatitis B were reported in Canada. It is generally accepted that the true incidence of the disease is about 10 times the reported incidence.

Hepatitis B virus is a major cause of acute and chronic hepatitis, cirrhosis and primary hepatocellular carcinoma. Chronic hepatitis may develop in 10% of infected adults and 90% of infected infants and may progress to cirrhosis and hepatocellular carcinoma. In its acute form hepatitis B is fatal in a small number of cases. The disease is transmitted through sexual contact and infected blood and other body fluids. Carriers frequently show no symptoms until later in life and may therefore infect others unknowingly.

Hepatitis B vaccine has been used in populations that have an established risk of infection with known consequences (e.g., health care workers, male homosexuals and injection drug users).

Recent attention in the Canadian press has focused on the possible association between hepatitis B vaccination and chronic fatigue syndrome (CFS).

You can read the rest of this article here: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1488229/pdf/cmaj00290-0039.pdf

 

Source: [No authors listed] Alleged link between hepatitis B vaccine and chronic fatigue syndrome. CMAJ. 1992 Jan 1;146(1):37-8. http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1488229/

 

Risk factors associated with chronic fatigue syndrome in a cluster of pediatric cases

Abstract:

After seven pediatric cases of chronic fatigue syndrome (CFS) were diagnosed in a farming community in upstate New York, a questionnaire regarding symptoms and potential risk factors of CFS was distributed to all students enrolled in the same school district.

Twenty-one students with symptoms of CFS were identified. Two controls per case matched for age and sex were randomly selected from questionnaire respondents. Health status was verified for all subjects by telephone, and diagnosis of CFS was confirmed by a physician.

Information was collected on the following factors: symptoms of CFS among other family members; history of allergy/asthma; consumption of raw milk, raw eggs, raw cheese, or raw meat; water supply; exposure to animals; home heating source; proximity to farmland/orchards; tick bite; blood transfusion; camping; and appendicitis.

Logistic-regression analyses indicated that the best model (characterized by symptoms among other family members, recent ingestion of raw milk, and history of allergy/asthma) produced significant estimates of relative risk (P less than .05) of 35.9, 44.3, and 23.3, respectively, for the three factors (corrections were made for the effect of the other covariates).

These data suggest that a combination of host and environmental factors, including an infectious agent or agents, are involved in the etiology of CFS.

 

Source: Bell KM, Cookfair D, Bell DS, Reese P, Cooper L. Risk factors associated with chronic fatigue syndrome in a cluster of pediatric cases. Rev Infect Dis. 1991 Jan-Feb;13 Suppl 1:S32-8. http://www.ncbi.nlm.nih.gov/pubmed/2020801

 

Molecular approaches to epidemiologic evaluation of viruses as risk factors for patients who have chronic fatigue syndrome

Abstract:

One approach to understanding the chronic fatigue syndrome might be to carry out prospective studies of fatigue that occurs following infection with viral diseases of known etiology, such as influenza, hepatitis, and infectious mononucleosis. Among the viral parameters that should be evaluated are virus burden, variation of virus strain, sites of viral replication, and the state of the viral life cycle (e.g., latent or replicative). Immunologic studies should focus on the humoral and cellular responses to defined viral gene products to identify subtle, individual variations in immune recognition of specific viral subcomponents.

 

Source: Miller G. Molecular approaches to epidemiologic evaluation of viruses as risk factors for patients who have chronic fatigue syndrome. Rev Infect Dis. 1991 Jan-Feb;13 Suppl 1:S119-22. http://www.ncbi.nlm.nih.gov/pubmed/1850537