Influenza notifications from some of our more northerly members such as the Bahamas, Bermuda and the Cayman Islands, were also significantly higher during this quarter, with peak transmission being observed after

epidemiologic week 50 [Figures 3a; 3b; 3c]. This pattern of reported morbidity is not unexpected and could be linked to the influx of tourists from areas such as Europe and North America, where epidemic influenza activity was occurring [United Kingdom Public Health Laboratory Surveillance Reports; Sentiweb, France; FluWatch, Canada; Morbidity and Mortality Weekly Report, USA].

Influenza virus A [H3N2 strain] was the most frequently recovered isolate in Europe and North America, where dramatic increases in reported morbidity were recorded during this influenza season as compared with the previous one. For example, in Scotland, general practitioner consultations for influenza and influenza–like illnesses reached a rate of 839 consultations per 100,000 population during first epidemiologic week of 2000.

Although the overall reported incidence of dengue fever during the fourth quarter was significantly lower [1,643 cases] than that recorded during the corresponding period of 1998 [2,885 cases], marked activity was noted in Suriname and Barbados [Figure 4]. National annual incidence rates of 281 and 316 cases per 100,000 population were recorded in Barbados and Suriname, respectively, during 1999.

In Suriname, an outbreak involving both DEN-1 and DEN-2 virus types began in the city of Paramaribo, during the period under review. There was subsequent spread to the surrounding districts of Commewijne, Para and Wanica. Between September and December 1999, 504 cases were notified from Suriname’s hospital surveillance system, which covers four hospitals in Paramaribo. In addition, 400 suspected cases were reported from their "telefonade" surveillance network, which is comprised of thirty sentinel stations located in the coastal areas of Suriname. Seventy percent of the stations in this network are primary health care centers, while 30.0% are general practitioners in private practice.

During 1999, all four dengue serotypes were found to be circulating in CAREC member countries, as identified by our laboratories. Dengue virus type 3 was recovered in St. Christopher/Nevis, Barbados and Belize. In the French Departments of the Americas, the first documented occurrence of an indigenous case of dengue fever due to DEN-3 infection was notified from Martinique in November 1999, by the French Institute for Public Health Surveillance [CIRE/InVS]. Similarly, four indigenous cases of DEN-3 infection were also recorded in French Guiana during December 1999. No increase in the reported number of classical cases of dengue fever or dengue haemorrhagic fever/shock syndrome has been observed in the French departments, since the detection of circulating type 3 virus.

Although malaria remains endemic in three CAREC member countries, namely, Belize, Guyana and Suriname, an increase in the reported incidence of imported infections has been observed in some island populations. This situation warrants concern as competent Anopheles species are present in most of the islands and would facilitate the re-introduction of this disease if persons with circulating parasites are available. In the endemic territories, transmission cycles involving both Plasmodium vivax and falciparum falciparum species currently occur.

During the fourth quarter of 1999, 13 cases of imported malaria were notified to CAREC’s Epidemiology Division from the Bahamas, Trinidad and Tobago, Antigua/Barbuda and the Cayman Islands. Cumulatively for the sub-region, 43 imported cases were recorded during 1999, representing a 59.0% increase over the 1998 notifications. The greatest proportion of these cases, 30 or 70.0%, was recorded by Bahamas, while the remaining cases were notified from Trinidad and Tobago [6 cases], the Cayman Islands [4 cases], St. Lucia [2 cases] and Antigua/Barbuda [1 case] [Figure 5].

Countries are being reminded of the need for 

Measles

During the period under review, 95 suspected cases of measles were notified to CAREC through the MESS system, but none of these suspected referrals were confirmed as measles by CAREC’s EPI laboratories. Caribbean public health practitioners are, however, being reminded of the important need for maintenance of the febrile rash surveillance system as well as continued vigilance as regards their national vaccination coverage rates. Recent outbreaks of measles have been confirmed in some European countries and, hence, the potential for importation into the Caribbean is not far-fetched theory. One outbreak of measles was recently reported in the Netherlands among traditionalist religious communities, who do not accept immunization [Eurosurveillance Weekly, Volume 3: 40, 1999], while another occurred in an infant population in the eastern part of the Republic of Ireland, where coverage rates of less than 75.0%, had been achieved [Eurosurveillance Weekly, Volume 4: 6, 2000].

During the fourth quarter of 1999, a total of 10,884 cases of gastroenteritis [inclusive of cases of unspecified age] were notified to CAREC’s Epidemiology Division, representing a 16.0% increase in reported morbidity over that for the corresponding period of 1998. Significant differences in reported morbidity between 1998 and 1999 were observed in the Cayman Islands, where 420 cases were notified during 1999, as compared with 47 reported cases during the fourth quarter of 1998.

Dr. MJ Lewis, Dr. S Aldighieri, Dr. E Boisson and Team

March, 2000

IMPORTANT REMINDER