Ispitivanje potencijalnih sentinel vrsta životinja u nadzoru groznice Zapadnog Nila
Investigation of potential sentinel species for the West Nile fever surveillance
Докторанд
Živulj, AleksandarМентор
Radojičić, SonjaЧланови комисије
Petrović, Tamaš![](/themes/MirageNardus/images/orcid.png)
Nišavić, Jakov
Milićević, Vesna
Šipetić-Grujičić, Sandra
![](/themes/MirageNardus/images/orcid.png)
Метаподаци
Приказ свих података о дисертацијиСажетак
groznicu Zapadnog Nila. Virus Zapadnog Nila je prvi put identifikovan 1937. godine u
Ugandi, oblast West Nile, u uzorku krvi žene koja je ispoljila kliničke simptome
povišene telesne telesne temperature.
Virus Zapadnog Nila se prenosi i održava u prirodi u ciklusu komarac – ptica gde su
ptice rezervoari virusa i prirodni domaćini. Konji i ljudi su slučajni domaćini virusa,
mogu klinički oboleti ali nemaju titar virusa u krvi koji bi inficirao komarce. Oko 25%
obolelih ljudi ispoljava povišenu telesnu temperaturu, a manje od 1% obolelih ljudi
ispoljava neurološke poremećaje. Kod konja dolazi do ispoljavanja simptoma oboljenja
nervnog sistema a u nekim slučajevima i do uginuća.
Pojava serokonverzije izazvane virusom Zapadnog Nila je utvrđena kod konja, ljudi,
kokoši, goveda, pasa, svinja, magaraca, koza, ptica poput golubova, vrabaca i drugih
domaćih i divljih životinja. Osnovni zadatak sprovođenja programa nadzora groznice
Zapadnog Nila jeste pravovremeno otkrivanje prisustva i cirkulac...ije virusa na nekom
području, kao i određivanje početka sezonske cirkulacije virusa u enzootskim
područjima u cilju blagovremenog informisanja, kontrole vektora i preveniranja
infekcije ljudi i životinja i sprečavanja pojave epidemija i epizootija.
Cilj ispitivanja ove doktorske disertacije bio je da se ispita svrsishodnost
postojećeg programa nadzora virusa Zapadnog Nila kao sistema ranog upozoravanja
(„early warning system“) i utvrdi prostorna i vremenska korelacija nalaza proisteklih iz
postojećeg sistema monitoringa u odnosu na pojavu bolesti kod ljudi, kao i da se ispita
mogućnost korišćenja goveda, svinja i živine kao sentinel vrsta životinja za efektivniji
nadzor groznice Zapadnog Nila.
Ukupno je ispitano 140 zbirnih uzoraka komaraca, 319 uzoraka krvnog seruma
konja, 76 uzoraka poreklom od divljih ptica (faringealni brisevi, mozak i druga tkiva),
168 uzoraka krvnog seruma goveda, 124 uzoraka krvnog seruma svinja i 125 uzoraka
krvnog seruma živine. Prikupljanje uzoraka vršeno je u periodu 2017.-2019. godina, na
više lokaliteta u više opština Južnobanatskog okruga u Republici Srbiji.
Ispitivanjem 140 zbirnih uzoraka komaraca metodom real time RT-PCR
utvrđeno je prisustvo nukleinske kiseline virusa Zapadnog Nila kod 22 uzorka (15,7%),
s tim da postoji značajna razlika u broju pozitivnih slučajeva u 2018. godini (15) u
odnosu na 2017. godinu (7). Test odnosa šansi pokazuje da je šansa otkrivanja
pozitivnih uzorka u 2018. godini bila 2,8 puta veća u odnosu na 2017. godinu.
Ispitivanjem 319 uzoraka krvnog seruma konja utvrđeno je prisustvo IgM antitela protiv
virusa Zapadnog Nila kod dva konja (0,6%), po jedan u 2017. i 2018. godini. Od 76
ispitanih uzoraka poreklom od divljih ptica metodom real time RT-PCR utvrđeno je
prisustvo nukleinske kiseline virusa Zapadnog Nila kod jedne divlje ptice – siva vrana
(1,3%). Ispitivanjem 105 uzoraka krvnog seruma goveda utvrđeno je prisustvo
specifičnih antitela protiv virusa Zapadnog Nila kod 48 goveda (45,6%), od kojih je
najviša seroprevalencija od 66,7% na farmi u naseljenom mestu Starčevo, na farmi u
Mramorku 46,7%, a na farmi u Pančevu 35%...
West Nile virus belongs to the Flaviviridae family, genus Flavivirus, and causes
West Nile fever. West Nile virus was first identified in 1937 in Uganda, West Nile
region, in a blood sample of a woman who was presented with clinical symptoms of
fever.
West Nile virus is transmitted and maintained in nature in the mosquito-bird
cycle, where birds are reservoirs and natural hosts of the virus. Horses and humans are
“dead-end” hosts of the virus; they can be clinically ill but do not have a titer of the
virus in their blood that would infect mosquitoes. About 25% of infected people show
fever, and less than 1% show neurological disorders. In horses, the symptoms of the
nervous system disease are manifested, and in some cases with fatal outcome.
The appearance of seroconversion caused by West Nile virus has been seen in
the horses, humans, chicken, cattle, dogs, pigs, donkeys, goats, birds such as pigeons
and sparrows, and other domestic and wild animals. The main task of the West Nile
fev...er surveillance program is to detect presence and circulation of the virus in the area,
as well as to recognize the beginning of seasonal circulation of the virus in enzootic
areas in order to provide timely information, control of vectors and to prevent human
and animal infections, epidemics and epizootics.
The aim of the present doctoral dissertation was to examine the effectiveness of
the existing West Nile virus surveillance program as an early warning system and to
determine the spatial and temporal correlation of the findings from the existing
monitoring system in relation to the occurrence of the disease in humans, as well as to
examine the possibility of using cattle, pigs and poultry as sentinel species for more
effective surveillance of West Nile fever.
A total of 140 pooled samples of mosquitoes, 319 blood serum samples from
horses, 76 samples from wild birds (pharyngeal swabs, brain and other tissues), 168
bovine blood serum samples, 124 pig blood serum samples, and 125 poultry blood
serum samples were examined. The samples were collected in the period from 2017 to
2019, at several sites and municipalities of the South Banat District in the Republic of
Serbia.
Examination of 140 pooled samples of mosquitoes by real-time RT-PCR
revealed the presence of West Nile virus nucleic acid in 22 samples (15.7%), with a
significant difference in the number of positive cases in 2018 (15) compared to 2017
(7). Odds ratio test shows that the chance of detecting positive samples in 2018 was 2.8
times higher than in 2017. Examination of 319 blood serum samples from horses
showed the presence of IgM antibodies against West Nile virus in two horses (0.6%),
one in 2017 and one in 2018. Out of 76 examined samples originating from wild birds
by real-time RT-PCR, the presence of West Nile virus nucleic acid was determined in
one wild bird - grey crow (1.3%). Examination of 105 blood serum samples from cattle
revealed the presence of specific antibodies against West Nile virus in 48 animals
(45.6%), with the highest seroprevalence (66.7%) on the farm in Starčevo, followed by
the seroprevalence of 46.7% on the farm in Mramorak and 35% on the farm in Pančevo...