Swine Influenza A at Fort Dix, New Jersey (January–February 1976). III. Extent of Spread and Duration of the Outbreak

• Published in: The Journal of infectious diseases 1977-12, Vol.136 (Supplement-3), p.S369-S375
• Main Authors: Hodder, Richard A., Gaydos, Joel C., Allen, Richard G., Top, Franklin H., Nowosiwsky, Taras, Russell, Philip K.
• Format: Article
• Language: English
• Subjects: Antibodies; Antibodies, Viral - biosynthesis; Antigens; Blood; Disease transmission; Female; Forts; Hemagglutination Inhibition Tests; Humans; Infections; Influenza A virus - isolation & purification; Influenza, Human - epidemiology; Influenza, Human - transmission; Male; Military Medicine; Military training; New Jersey; Orthomyxoviridae; Session I. Early Events; Soldiers; Viruses
• ISSN: 0022-1899; 1537-6613
• DOI: 10.1093/infdis/136.Supplement_3.S369

The extent and duration of transmission of influenza A/New Jersey/76 virus at Fort Dix, New Jersey, was examined with use of titers of hemagglutination-inhibiting antibody to influenza A/Mayo Clinic/74 (Hsw1N1) antigen as an index of infection. Five hundred ninety-three soldiers (a 9.3% sample) in basic combat training (BCT) were grouped in weekly cohorts by the date on which BCT was started. Cohorts with 11 of the 12 BCT cases of A/swine influenza began training on January 12, 19, and 26, 1976, respectively; 9%–19% of the trainees in these cohorts had titers of antibody to A/Mayo Clinic antigen of ⩾1:20. In five other cohorts without cases, which began training before January 12 or after January 26, 0–5% of trainees had titers of ⩾1:20. Titers observed in persons from military units not in BCT and in the civilian population of the post were not consistent with widespread transmission of the virus. Transmission of influenza A/New Jersey virus at Fort Dix probably occurred between mid-January and mid-February with little involvement of people ouside of BCT units.