A/Victoria Influenza

Fifteen states have reported widespread outbreaks of influenza according to a CDC telephone survey begun February 19, 1976 (Figure 1). Another 18 states reported regional involvement, and 14 others reported isolated cases. Three states recorded no reported cases.

The most heavily affected areas in the country so far this year continue to be the New England and Middle Atlantic states, as reflected by excess mortality. The Pacific and Mountain regions show pneumonia and influenza (P and I) deaths above the epidemic threshold for the first time. The total P and I mortality for the nation increased again this week. Excess mortality has not been observed in the remaining 5 regions.

Except for the swine-like influenza virus isolates reported below, the previously reported isolates of influenza B, and the 1 isolate resembling A/Tokyo/1/75 (MMWR 25 [5]), all isolates reported to CDC from state health departments and cooperating laboratories have been the A/Victoria strain. Clinical disease appears to be identical to previous outbreaks of influenza in the United States, namely, fever, respiratory symptoms, and myalgia, with occasional reports of gastrointestinal symptoms, particularly in younger children.

New Jersey: As previously reported (MMWR 25[6]), 4 isolates of A/swine-like virus were isolated from 3 recruits and 1 staff soldier at Fort Dix, New Jersey, in early February. As a follow-up to these isolations, intensive surveillance of respiratory disease at Fort Dix and surrounding areas has been undertaken. One additional isolate of swine-like virus has been reported from a Fort Dix soldier. Six additional seroconversions from Fort Dix were detected, bringing the total number of confirmed cases to 11. Illness in the earliest of these cases appears to have started the third week of January.

Preliminary results of a serosurvey conducted at Fort Dix showed positive HI titers in 68 of 308 (22%) of sera tested. Positive HI titers were found in 34% of those in a platoon with confirmed cases; rates were as low as 6% in platoons without confirmed cases.

The New Jersey State Department of Health has instituted intensive influenza surveillance throughout the state, with concentrated efforts in the county surrounding Fort Dix.

To date, over 70 isolates of influenza A have been obtained; all of these civilian isolations were A/Victoria-like.

Tennessee: As a result of the report of swine-like influenza isolations at Fort Dix, several hundred sera collected for other purposes in Tennessee were screened for antibodies to the swine-like virus. One positive specimen was found; it had been taken from a young Mississippi male with Hodgkin's disease who recently worked in a swine slaughterhouse. Investigation of the patient's contacts is underway.

Wisconsin: During the week of February 17, local and state health personnel investigated the contacts of the 8-yearold Wisconsin farm boy whose acute and convalescent sera had shown an antibody rise to swine-like influenza virus in October 1975 (MMWR, 25[6]). A total of 245 sera were obtained from family members, school contacts, and other members of the community. Preliminary results indicate that 5 out of 7 family members have positive HI titers (1:20) to swine-like virus; 136 school children, including all classmates of the boy, were negative. Eight of 64 (13%) of community members under 50-years-old were positive; 33 of 38 (87%) of those 50 and older had positive titers to swine-like virus.

The World Health Organization has notified all collaborating laboratories of the swine-like isolates from Fort Dix and requested that efforts be made to determine if swinelike viruses have occurred elsewhere in the world. To date, no isolations have been reported.

(Reported by M Goldfield, MD, R Altman, MD, State Epidemiologist, New Jersey Dept of Health; J Bartley, Col, Health and Environment, USAMEDDAC, Ft Dix, NJ; T Nowosiwsky, Col, Div of Preventive Medicine, PK Russell, Col, Div of Communicable Disease and Immunology, FH Top, Jr, Col, Dept of Virology, Walter Reed Army Institute of Research, Washington, DC; R Webster, PhD, St Jude's Children's Hospital, Memphis, Tenn; RH Hutcheson, Jr, MD, State Epidemiologist, Tennessee Dept of Public Health; C Sprangers, RN, Sheboygan County Nurses' Office, Sheboygan, Wis; HG Skinner, MD, State Epidemiologist, Wisconsin Dept of Health and Social Servcies, Div of Health; LJ Legters, Col, Health and Environment, Office of the Surgeon General Headquarters, Dept of the Army, Washington, DC; Virology Div, Bur of Laboratories, and Viral Diseases Div, Bur of Epidemiology, CDC.)

Editorial Note

A/Victoria influenza virus continues to be responsible for nearly all confirmed influenza outbreaks in the United States. Investigation of the 8-year-old boy from Wisconsin has documented exposure to A/swine-like virus in other family members. The absence of antibodies in the boy's school contacts suggests that there was no significant spread within the community. The results of the serological survey in Fort Dix, however, establish that person-to-person transmission of the swine-like virus occurred within the military setting. Investigations are continuing to determine the circumstances surrounding the introduction and spread of the virus in Fort Dix.

23,649, representing a 1.1% increase over the 23,389 such cases reported in the same time period of 1974. (Reported by the Venereal Disease Control Div, Bur of State Services, CDC.)

ANGIOSARCOMA - Continued

has been assembled through medical record review and family interview (Table 1). Particular attention has been given to potential occupational or environmental exposure to chemicals known to induce ASL (vinyl chloride, arsenic, and thorium dioxide).

Most cases (7 of 10) were diagnosed since 1970, probably reflecting better case ascertainment in recent years. Ages ranged from 36-71 (mean age 58 years). All but 1 patient were male, and all but 1 were white. Places of usual residence for all cases were widely scattered across the state, roughly corresponding with the state's population (Figure 1).

One patient had a history of prior thorium dioxide exposure. For none of the remaining cases was tumor etiology obvious. Occupations and histories of exposure to potential environmental toxins differed widely, with no more than 1 case associated with any particular industry or mode of exposure. In several instances, however, individual patient occupations or exposures were suggestive of possible oncogenicity (Table 1). Patient 10 had had exposure to a vinyl compound; he had worked in paper and plywood products with potential contact with various chemicals, including polyvinyl acetate. Two other patients gave histories of possible exposure to arsenic: patient 9, who had exposure to insecticides while farming, and patient 8, who worked with wood probably treated with arsenic preservatives in the manufacture of bleachers. All but 3 of the 10 patients were known to have lived on farms during their lifetimes, 2 for all of their lives (Table 1).

(Reported by J Fiechtner, MD, C Reyes, MD, Marshfield Clinic; K Rentmesster, MPH, HG Skinner, MD, State Epidemiologist, Wisconsin State Dept of Health and Social Services; Office of Extramural Coordination and Special Projects, National Institute of Safety and Health; and the Cancer and Birth Defects Div, Bur of Epidemiology, CDC.) Editorial Note

These data indicate no obvious common-source origins among recent cases of ASL in Wisconsin. The marked male preponderance among cases, however, suggests occupational

Figure 1

GEOGRAPHIC DISTRIBUTION OF CONFIRMED CASES OF ANGIOSARCOMA OF THE LIVER IN WISCONSIN RESIDENTS, 1964-1975, BY PLACE OF USUAL RESIDENCE

exposure as the potential origin for at least some of the cases. Anecdotal histories of occupational and environmental exposures in several of the cases may warrant further investigation, particularly in relation to contact with arsenic. Although at present only vinyl chloride monomer (1), thorium dioxide (2), and arsenic (3,4) are clearly implicated as causes of ASL, investigations such as the one described here may well provide useful leads in defining further causes. References

1. Creech JL, Johnson MN: Angiosarcoma of liver in the manufacture of polyvinyl chloride. J Occup Med 16:150-151, 1974

2. MacMahon HE, Murphy AS, Bates MI: Endothelial-cell sarcoma of liver following Thorotrast injection. Am J Pathol 23:585-595, 1947 3. Lender JJ, Stanly RJ, Sumner HW, et al: Angiosarcoma of the liver associated with Fowler's solution (potassium arsenite). Gastroenterology 68:1582-1586, 1975

4. Roth F: The sequela of chronic arsenic poisoning in Moselle vinters. Ger Med Mon 2:172-175, 1957