Epidemic Shigella dysenteriae in Mumias, western Kenya

Using European travellers as an early alert to detect emerging pathogens in countries with limited laboratory resources

Background

The volume, extent and speed of travel have dramatically increased in the past decades, providing the potential for an infectious disease to spread through the transportation network. By collecting information on the suspected place of infection, existing surveillance systems in industrialized countries may provide timely information for areas of the world without adequate surveillance currently in place. We present the results of a case study using reported cases of Shigella dysenteriae serotype 1 (Sd1) in European travellers to detect "events" of Sd1, related to either epidemic cases or endemic cases in developing countries.

Methods

We identified papers from a Medline search for reported events of Sd1 from 1940 to 2002. We requested data on shigella infections reported to the responsible surveillance entities in 17 European countries. Reports of Sd1 from the published literature were then compared with Sd1 notified cases among European travellers from 1990 to 2002.

Results

Prior to a large epidemic in 1999–2000, no cases of Sd1 had been identified in West Africa. However, if travellers had been used as an early warning, Sd1 could have been identified in this region as earlier as 1992.

Conclusion

This project demonstrates that tracking diseases in European travellers could be used to detect emerging disease in developing countries. This approach should be further tested with a view to the continuous improvement of national health surveillance systems and existing European networks, and may play a significant role in aiding the international public health community to improve infectious disease control.

Case management of a multidrug-resistant Shigella dysenteriae serotype 1 outbreak in a crisis context in Sierra Leone, 1999-2000

From December 1999 to the end of February 2000, 4218 cases of dysentery were reported in Kenema district, southeastern Sierra Leone, by a Médecins Sans Frontières team operating in this region. Shigella dysenteriae serotype 1 was isolated from the early cases. The overall attack rate was 7.5% but higher among children under 5 years (11.2%) compared to the rest of the population (6.8%) (RR = 1.6; 95% CI 1.5-1.8). The case fatality ratio was 3.1%, and higher for children under 5 years (6.1% vs. 2.1%) (RR = 2.9; 95% CI 2.1-4.1). A case management strategy based on stratification of affected cases was chosen in this resource-poor setting. Patients considered at higher risk of death were treated with a 5 day ciprofloxacin regimen in isolation centres. Five hundred and eighty-three cases were treated with a case fatality ratio of 0.9%. Patients who did not have signs of severity when seen by health workers were given hygiene advice and oral rehydration salts. This strategy was effective in this complex emergency.

Preparation of synthetic glycoconjugates as potential vaccines against Shigella flexneri serotype 2a disease

The synthesis of three neoglycopeptides incorporating carbohydrate haptens, differing in length, covalently linked to a non natural universal T helper peptide is disclosed. They were synthesized according to a blockwise strategy based on the condensation of appropriate di-, tri-, and tetrasaccharide trichloroacetimidate donors onto an azidoethyl 2-acetamido-2-deoxybeta-D-glucopyranoside acceptor. Use of thiol-maleimide coupling chemistry allowed site-selective efficient conjugation.

Emerging and reemerging infections in africa: the need for improved laboratory services and disease surveillance

Emerging and reemerging infections pose a serious public health threat to most countries of tropical Africa. In the past decade, epidemics of diseases including cholera, dysentery, meningitis, yellow fever and Ebola virus have resulted in significant morbidity and mortality. Improved laboratory services and disease surveillance systems are essential to monitor disease trends and to initiate public health action. The present situation of emerging and reemerging infections in Africa is described in this review, and strategies for improved disease surveillance and monitoring are discussed.