Surveillance for Alouatta monkeys in the forests of Trinidad, 1988-1989

A continuous surveillance programme for the presence of the red howler monkeys (Alouatta sp.) in the forests of Trinidad was initiated following an epizootic of yellow fever in these monkeys in 1978. This paper gives the result of the programme from 1986 to 1989 (AU)

Entomological activities during the yellow fever epidemic in Trinidad, 1978-1980

An epidemic of sylvan yellow fever occurred in Trinidad during the period 1978 to 1980. Entomological activities were initiated at various localities where monkey (Alouatta spp.) mortalities were reported. A total of 5,468 Haemagogus janthinomys was collected and tested which resulted in the isolation of 17 strains of yellow fever virus. Two strains of the virus were isolated from a total of 49 Haemagogus leucocelaenus and these constituted the first isolations of yellow fever virus from this species of mosquito from Trinidad. Attempts to demonstrate transovarial transmission of yellow fever virus from adults feared from eggs and larvae collected in the field were unsuccessful. However, from two locations virus isolations were made at the end of rainy season (January) and at the beginning of the successive rainy season (June) (AU)

Monitoring of Alouatta monkeys as an early warning system in yellow fever surveillance

An epizootic of yellow fever occurred in Alouatta monkeys in November 1978. An intensive surveillance programme was initiated to locate sick and dying monkeys in the forests of Trinidad. Thirty Alouatta (red howler)monkeys were collected and examined for yellow fever virus. Sixteen of the monkeys were positive for the virus and these came from south-east, east, and north-west Trinidad (AU)

Laboratory diagnosis of yellow fever infections in humans, alouatta monkeys and haemagogus mosquitoes in Trinidad, 1978-1980

The yellow fever epidemic in Trinidad began with an epizootic in alouatta monkeys in November, 1978. Activity was detected by virus isolation from Alouatta monkeys and from Haemagogus mosquitoes between this date and July 1980. First reports of monkey deaths centered around the Guayaguayare forests of South Trinidad, following which the epizootic spread west to the Moruga area, and north through the Biche Forest reserve, eventually reaching the north-west Chaguaramas peninsula. Surveillance of febrile persons attending clinics and hospitals was intensified and 18 confirmed cases were identified, from 14 of whom yellow fever virus was isolated. In four cases, diagnoses were made on the basis of liver pathology only. Paired sera were obtained from 10 of 11 persons who survived, and in each case serological conversions were obtained by haemagglutination inhibition and mouse neutralization tests. Yellow Fever virus was isolated from 16 of 32 Alouatta monkeys and from 19 of 174 pools of Haemagogus mosquitoes. Two systems were used for virus isolation: the Aedes cell line AP-61 and suckling mice. The former proved to be more sensitive, detecting virus in 11.7 percent of 725 specimens inoculated whereas suckling mice detected virus in 7.9 percent of 724 specimens. In 11 instances virus was detected in an animal or mosquito pool by AP-61 but not initially by mouse inoculation whereas the converse was true in only one case (AU)

Surveillance and management of sylvatic yellow fever in Trinidad (1988-1989) - abstract

Howler monkey (Aloutta sp) deaths in the Southeastern forests of Trinidad were reported in December, 1988. This paper reports the laboratory and field investigations and preventive measures which were undertaken, in view of the known association between such deaths and yellow fever (YF) activity. A total of 47,640 adult mosquitoes were captured in several forest regions in Trinidad during the period December 1988 to October, 1989. Mosquitoes were identified, pooled and processed for virus isolation. Blood and organs from 5 dead Howler monkeys submitted between December 1988 and March, 1989 were examined for the presence of YF virus. Virus isolation was done by innoculation of material in AP61 (Ades pseudo-scutellaris) tissue culture and in 2-day-old Swiss albino mice, followed by identification of YF isolates by immunoflourescence, using monoclonal antibody and standard mouse neutralization tests, respectively. Fourty-four species of mosquito belonging to 14 genera were identified. From 654 mosquito pools, 6 YF isolates were obtained from only 2 species: five isolates from haemagogus janthinomys (December, 1988) and 1, for the first time locally, from Sabethes chloropterus (January, 1989). YF virus was isolated from blood and organs of 2 Howler monkeys captured on February 22 and March 2, 1989. There were no human cases of YF. Yellow fever activity appeared to be confined to the southeast part of the island. Preventive measures included mass targeted YF immunization (400,000 doses administered in 3 months), intensified vector control operations and reduced human contact with forest mosquitoes by the existing ban on hunting (AU)

Eosinophilic meningoencephalitis due to Angiostrongylus cantonensis as the cause of death in captive non-human primates

Fatal eosinophilic meningoencephalitis due Angiostrongylus cantonensis is reported in captive non-human primates. A howler monkey (Alouatta caraya) at the Audubon park and Zoological Gardens, New Orleans,LA, died 21 days after initial clinical symptoms. A white-handed gibbon (Hylobates lar) died at the Ardastra Gardens and Zoo, Nassau, Bahamas, 17 days after onset of symptoms. Both had access to free-ranging by A.cantonensis in non-human primates in the western hemisphere. (AU)

Sylvatic yellow fever activity in Trinidad, 1988-1989

Of a total of 18,068 mosquitoes (361 pools) collected in south-eastern Trinidad forests from December 1988 to May 1989, 47 species belonging to 14 genera were identified. Five yellow fever virus isolates were made from Haemagogus janthinomys and one from Sabethes chloropterus. All the other pools of mosquitoes examined were negative for the virus. The mosquito isolates were made in December and January. In addition, in late February and early March, 2 infected howler monkeys (Alouatta sp.) were detected. Since March, despite continued surveillance, no yellow fever virus has been detected in mosquitoes or monkeys. There has been no reported human imfection. (AU)

The isolation of yellow fever virus from the livers of naturally infected red howler monkeys

Yellow fever virus has been isolated from the liver of seven naturally infected red howler monkeys found dead or dying in the forest. The pathological lesions in these livers were typical of yellow fever.(Summary).

Oropouche virus: a new human disease agent from Trinidad, West Indies

The isolation and laboratory studies of a new virus isolated from a human fever case in Trinidad, West Indies, are described. The virus has been named Oropouche virus after the region from which it was obtained. Oropouche virus has been to be related to Simbu virus, an agent isolated in South Africa. Neutralizing antibodies were found in the blood of a few forest workers, 8 of 26 native cebus monkeys in the Nariva Swamp and 9 of 26 howler monkeys widely distributed over the island. (Summary)

Epidemiological notes in connection with the 1954 outbreak of yellow fever in Trinidad, B.W.I

A brief history of the 1954 yellow fever outbreak in Trinidad, B.W.I., is presented. Special emphasis is laid upon difficulties in recognition of mild cases of yellow fever in the field. It is suggested that prompt recognition of the epidemic threat and early instition of control measures averted a serious epidemic. (Summary)

Activities of the Trinidad regional virus laboratory in 1953 and 1954 with special reference to yellow fever outbreak in Trinidad, B.W.I

Serological surveys of Trinidad residents by the Trinidad Regional Laboratory demonstrated yellow fever immunes in eight individuals 15-19 years of age, and in a high proportion of older individuals. Yellow fever virus was isolated from a human case in April 1954. Subsequently virus isolations have been made from 13 other human cases, 7 red howler (Alouatta) monkeys which were brought in dead, 21 pools of Haemogogus mosquitoes, and 1 pool of mixed mosquitos -a total of 43 virus isolations. Yellow fever virus was repeatedly recovered from Haemogogus mosquitoes captured at ground level. (Summary)

Manzanilia virus: a new virus isolated from the blood of a howler monkey in Trinidad, W. I.

The isolation and laboratory studies of an unidentified virus isolated from a howler monkey in Trinidad, W. I., have been described. The virus has been named "Manzanilla virus" after the region from which it was obtained. The absence of virus-neutralizing antibodies from the sera of a number of forest workers would seem indicate that this virus probably is not a frequent cause of infection in man (Summary)

The isolation of yellow fever virus from the livers of naturally infected red howler monkeys

Yellow fever virus has been isolated from the liver of each of seven naturally infected red howler monkeys found dead or dying in the forest. The pathological lesions in these livers were typical of yellow fever (Summary)

The history of yellow fever

An historical overview of yellow fever dating back to the 18th and 17th centuries. The author looks at the history of the first outbreak in Trinidad where Trinidad is specifically named in 1793. The paper highlights the key role that Trinidad has played in the unravelling of yellow fever epidemiological mysteries. Recorded and suspected outbreaks of yellow fever is also presented in table form