4 years and 15-19 years had the highest incidence rates (4.1/100,000 each); the 10- to 14-year age group had the next highest (3.0/100,000).

Complications were reported in 351 (13.5%) of the 2,595 cases. Otitis media was reported in 175 (6.7%) cases; diarrhea, in 129 (5.0%); pneumonia, in 68 (2.6%); and encephalitis, in 2 (0.1%). Two hundred and one (7.7%) of these patients were hospitalized. Four deaths were attributed to measles, for a death-to-case ratio of 1.5:1,000. All four patients were immunocompromised. Two were 4-year-olds with acquired immunodeficiency syndrome; one was a 9-year-old who had autoimmune hemolytic anemia and was receiving corticosteroid therapy; and one was a 57-yearold with chronic lymphocytic leukemia. Two cases were acquired in the hospital, and two were acquired in the community.

Of the 1,805 (69.6%) patients for whom setting of transmission was reported, 960 (53.2%) acquired measles in primary or secondary schools; 122 (6.8%), in colleges

FIGURE 1. Reported measles cases, by week of rash onset weeks, 1987

TABLE 1. Reported measles cases and estimated incidence rates* of measles, by age of patients - United States, first 26 weeks, 1986 and 1987

*Rates per 100,000 population are based on provisional data for both years.
*Estimated total excludes 20 reported cases for which the age group was unknown.

or universities; 386 (21.4%), at home; 114 (6.3%), in medical settings; 31 (1.7%), in day-care centers; and 192 (10.6%), in a variety of other settings including work, church, and the military.

A total of 1,274 (49.1%) patients had been vaccinated on or after their first birthdays. This group included 427 (33.5%) who were vaccinated at 12-14 months of age. There were 1,213 (46.7%) unvaccinated patients and 108 (4.2%) with histories of vaccination before their first birthdays.

Of the 2,595 cases, 704 (27.1%) were classified as preventable (2), and 1,891 (72.9%), as nonpreventable (Tables 2, 3). Between 1986 and 1987, the absolute number and proportion of preventable cases decreased for all except the over 25-year age group. The highest proportion of preventable cases occurred among persons not of school age-87.5% of cases among adults 25-29 years of age and 68.2% of cases among children 16 months through 4 years of age were preventable. Two hundred sixty-six (37.8%) of the total number of preventable cases involved children 5-19 years of age, and 17.8% of the total cases in this age group were preventable. Cases among adequately vaccinated persons constituted 67.0% of nonpreventable cases and 48.8% of total cases (Table 3). Of the 1,497 school-aged children who acquired measles, 1,119 (74.7%) had been adequately vaccinated, and 406 (27.1%) had been vaccinated at 12-14 months of age.

Reported by: Div of Immunization, Center for Prevention Svcs, CDC.

Editorial Note: After the record low of 1,497 measles cases in 1983, the number of measles cases increased each year through 1986. The number of cases reported for the first 26 weeks of 1987 is less than that reported during the comparable period in 1986 and reverses this trend. The incidence rates have decreased in all except the 15to 19-year age group. The increase in this group was attributable to several large outbreaks in secondary schools and colleges.

$Includes two adequately vaccinated patients who were born before 1957 and five who were less than 16 months of age.

TABLE 2. Preventability of measles cases, by age of patients weeks, 1986 and 1987*

The four deaths due to measles during the first half of 1987 are the first reported to the Division of Immunization since 1985 (3). All four cases either initiated or were part of nosocomial outbreaks involving medical personnel. In addition, a higher proportion of cases were acquired in medical settings in 1987 than in previous years (4-6). The deaths, combined with the increased proportion of cases acquired in medical settings, highlight the role of these settings in the transmission of measles and emphasize the need for immunization requirements for medical personnel at risk of exposure (7,8).

As in previous years, a large proportion of persons who acquired measles had been vaccinated. In an effort to decrease the occurrence of these cases, changes in the current immunization strategy are being discussed. In many outbreaks, persons vaccinated at 12-14 months of age have been demonstrated to be at slightly higher risk for measles than persons vaccinated at 15 or more months of age. Therefore, the Immunization Practices Advisory Committee (ACIP) recently recommended that revaccination of persons previously vaccinated at 12-14 months of age be considered during outbreaks (8,9). Most cases of measles among persons who received vaccine at 15 months of age or older appear to be the result of primary vaccine failure and not of waning immunity (10).

The two major impediments to measles elimination in the United Statesunvaccinated preschoolers and vaccine failure in the school-aged populationrequire different solutions. Health-care providers should take advantage of every opportunity to vaccinate these children (11). Measles-containing vaccines should be administered to eligible children regardless of the need for other vaccines. The ACIP now recommends simultaneous administration of MMR, DTP, and OPV at 15 months of age (12), both routinely and for children behind on their immunization schedules. The number of vaccine failures among children 5-19 years of age has stimulated efforts to devise strategies to reduce the rate of primary vaccine failure. CDC is

convening a group of consultants to review the current status of efforts to eliminate measles in the United States and to discuss potential modifications (13) to the current strategies. These modifications include revaccination, either routinely, as a two-dose schedule, or selectively, as part of outbreak control.

References

1. Centers for Disease Control. Measles - United States, first 26 weeks, 1986. MMWR 1986;35:525-8,533.

2. Centers for Disease Control. Classification of measles cases and categorization of measles elimination programs. MMWR 1983;31:707-11.

3. Centers for Disease Control. Multiple measles outbreaks on college campuses - Ohio, Massachusetts, Illinois. MMWR 1985;34:129-30.

4. Davis RM, Orenstein WA, Frank JA, et al. Transmission of measles in medical settings: 1980 through 1984. JAMA 1986;255:1295-8.

5. Centers for Disease Control. Measles - United States, 1985. MMWR 1986;35:366-70.

6. Centers for Disease Control. Measles-United States, 1986. MMWR 1987;36:301-5.

7. Williams WW. Guideline for infection control in hospital personnel. Infect Control 1983;4(suppl):326-49.

8. Orenstein WA, Markowitz LE, Preblud SR, Hinman AR, Tomasi A, Bart KJ. Appropriate age for measles vaccination in the United States. Dev Biol Stand 1986;65:13-21.

9. Immunization Practices Advisory Committee. Measles prevention. MMWR 1987;36: 409-18,423-5.

10. Preblud SR, Markowitz LE, Orenstein WA. Update on measles vaccine effectiveness. Presented at the 21st immunization conference, New Orleans, Louisiana, June 8-11, 1987. 11. Hutchins SS, Escolan J, Markowitz LE, et al. An outbreak of measles among unvaccinated preschool-aged children. Presented at the American Public Health Association 115th annual meeting, New Orleans, Louisiana, October 18, 1987.

12. Immunization Practices Advisory Committee. New recommended schedule for active immunization of normal infants and children. MMWR 1986;35:577-9.

13. Orenstein WA, Hinman AR, Preblud SR, Markowitz LE. Additional strategies for measles elimination. Presented at the 21st immunization conference, New Orleans, Louisiana, June 8-11, 1987.

Perspectives in Disease Prevention and Health Promotion

Semen Banking, Organ and Tissue Transplantation,
and HIV Antibody Testing

The following recommendations regarding storage and use of semen were prepared by the Food and Drug Administration and the Centers for Disease Control with the endorsement of the American Association of Tissue Banks, the American Fertility Society, and the American College of Obstetricians and Gynecologists.

The Public Health Service published its initial recommendations regarding screening prospective donors of semen, organs, or tissues for the presence of antibody to human immunodeficiency virus (HIV) in 1985 (1). The role of donated semen in the transmission of HIV infection was confirmed later that year (2). In late 1986 and early 1987, transmission of acute viral hepatitis B resulting from artificial insemination with donated semen was reported (3,4). In April of 1987, an allogenic skin graft was implicated in the transmission of HIV infection (5). A month later, a cadaveric organ donor was found positive for antibody to HIV after his organs were transplanted (6). Most recently, the House of Delegates of the American Medical Association, at its

Semen Banking Continued

meeting held June 21-25, 1987, adopted a recommendation that testing for antibody to HIV be performed for all donors of blood, organs, or tissues intended for transplantation and for donors of semen or ova (7). Other professional organizations, such as the American Association of Tissue Banks and the American Fertility Society, have published standards and guidelines designed to prevent or minimize the possibility of transmitting disease through artificial insemination or allotransplants (8,9).

Based on current knowledge, the following recommendations are made with respect to organ and tissue transplantation and artificial insemination:

Prospective donors of organs, tissues, and semen should be tested for antibody to HIV (1,6). Tests for hospitalized donors should be run on a serum sample taken prior to the donor's receipt of any blood transfusions to avoid situations in which multiple transfusions might result in an antibody loss due to hemodilution (6). Organs and tissues from prospective donors found seropositive for HIV antibody should not be used except when the transplantation of an indispensable organ is necessary to save a patient's life.

TABLE II. Notifiable diseases of low frequency, United States