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. 1975;52(4-6):577–592.

Lassa fever: review of epidemiology and epizootiology

T P Monath
PMCID: PMC2366662  PMID: 782738

Abstract

The basic ecology of Lassa fever appears to involve enzootic transmission of virus in commensal populations of a single murine species, Mastomys natalensis. Virus may spill over from the rodent cycle to man by various routes. Secondary spread between humans may occur within domiciliary groups, and persons infected within the community who develop clinical disease may introduce the virus into hospital and begin a cycle of nosocomial infection.

Between 1969, when Lassa fever was first described, and June 1975, the disease was recognized on 9 discrete occasions, affecting 114 persons. Over one-third of these infections were acquired by person-to-person spread within hospitals. In only one outbreak (in Sierra Leone) were the majority of cases acquired in the community. Recent observations have indicated hyperendemic disease in eastern Sierra Leone. Cases have occurred in Nigeria, Sierra Leone, and Liberia, and serological evidence exists for activity of the virus elsewhere in West and Central Africa. Seasonal factors appear to play a role in the appearance of human cases. Attack rates have been higher in adults than in children. The source of infection and potential routes of virus transmission in the various epidemics are discussed, and perspectives for future epidemiological research are presented.

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Selected References

These references are in PubMed. This may not be the complete list of references from this article.

  1. Bellier L. The genus Mastomys in the Ivory Coast. Bull World Health Organ. 1975;52(4-6):665–665. [PMC free article] [PubMed] [Google Scholar]
  2. Bowen G. S., Tomori O., Wulff H., Casals J., Noonan A., Downs W. G. Lassa fever in Onitsha, East Central State, Nigeria in 1974. Bull World Health Organ. 1975;52(4-6):599–604. [PMC free article] [PubMed] [Google Scholar]
  3. Frame J. D., Baldwin J. M., Jr, Gocke D. J., Troup J. M. Lassa fever, a new virus disease of man from West Africa. I. Clinical description and pathological findings. Am J Trop Med Hyg. 1970 Jul;19(4):670–676. doi: 10.4269/ajtmh.1970.19.670. [DOI] [PubMed] [Google Scholar]
  4. Frame J. D. Surveillance of Lassa fever in missionaries stationed in West Africa. Bull World Health Organ. 1975;52(4-6):593–598. [PMC free article] [PubMed] [Google Scholar]
  5. Fraser D. W., Campbell C. C., Monath T. P., Goff P. A., Gregg M. B. Lassa fever in the Eastern Province of Sierra Leone, 1970-1972. I. Epidemiologic studies. Am J Trop Med Hyg. 1974 Nov;23(6):1131–1139. doi: 10.4269/ajtmh.1974.23.1131. [DOI] [PubMed] [Google Scholar]
  6. GIROUD P., LE GAC P., GANZIN M., GAILLARD J. A. Le typhus murin de l'Oubangui est grave; il mériterait le nom de tropical; son diagnostic peut être difficile; on peut y remédier par électrophorèse sur papier. Bull Soc Pathol Exot Filiales. 1952;45(3):306–310. [PubMed] [Google Scholar]
  7. Henderson B. E., Gary G. W., Jr, Kissling R. E., Frame J. D., Carey D. E. Lassa fever. Virological and serological studies. Trans R Soc Trop Med Hyg. 1972;66(3):409–416. doi: 10.1016/0035-9203(72)90272-6. [DOI] [PubMed] [Google Scholar]
  8. Henderson B. E., Gary G. W., Jr, Kissling R. E., Frame J. D., Carey D. E. Lassa fever. Virological and serological studies. Trans R Soc Trop Med Hyg. 1972;66(3):409–416. doi: 10.1016/0035-9203(72)90272-6. [DOI] [PubMed] [Google Scholar]
  9. Leifer E., Gocke D. J., Bourne H. Lassa fever, a new virus disease of man from West Africa. II. Report of a laboratory-acquired infection treated with plasma from a person recently recovered from the disease. Am J Trop Med Hyg. 1970 Jul;19(4):677–679. doi: 10.4269/ajtmh.1970.19.677. [DOI] [PubMed] [Google Scholar]
  10. Mertens P. E., Patton R., Baum J. J., Monath T. P. Clinical presentation of Lassa fever cases during the hospital epidemic at Zorzor, Liberia, March-April 1972. Am J Trop Med Hyg. 1973 Nov;22(6):780–784. doi: 10.4269/ajtmh.1973.22.780. [DOI] [PubMed] [Google Scholar]
  11. Monath T. P., Maher M., Casals J., Kissling R. E., Cacciapuoti A. Lassa fever in the Eastern Province of Sierra Leone, 1970-1972. II. Clinical observations and virological studies on selected hospital cases. Am J Trop Med Hyg. 1974 Nov;23(6):1140–1149. doi: 10.4269/ajtmh.1974.23.1140. [DOI] [PubMed] [Google Scholar]
  12. Monath T. P., Mertens P. E., Patton R., Moser C. R., Baum J. J., Pinneo L., Gary G. W., Kissling R. E. A hospital epidemic of Lassa fever in Zorzor, Liberia, March-April 1972. Am J Trop Med Hyg. 1973 Nov;22(6):773–779. doi: 10.4269/ajtmh.1973.22.773. [DOI] [PubMed] [Google Scholar]
  13. Monath T. P., Newhouse V. F., Kemp G. E., Setzer H. W., Cacciapuoti A. Lassa virus isolation from Mastomys natalensis rodents during an epidemic in Sierra Leone. Science. 1974 Jul 19;185(4147):263–265. doi: 10.1126/science.185.4147.263. [DOI] [PubMed] [Google Scholar]
  14. Wulff H., Fabiyi A., Monath T. P. Recent isolations of Lassa virus from Nigerian rodents. Bull World Health Organ. 1975;52(4-6):609–613. [PMC free article] [PubMed] [Google Scholar]

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