Rev. Bio!. Trop., 45(3): 989-991, 1997

Rotavirus and coronavirus outbreak: etiology of annual diarrhea in Costa Rican children

' 2 3 ' Paulina González, Abelino Sánches , Patricia Rivera , Carlos Jiménez and Francisco Hemández 1 Facultad de Microbiología, Universidad de Costa Rica, San José, Costa Rica. Servicio de Patología, Hospital Nacional de Nifios, San José, Costa Rica. Programa de Investigación en Enfermedades Tropicales (PIET), Escuela de Medicina Veterinaria, Universidad Nacional, Heredia, Costa Rica. *Corresponding author.

(Received l-XII-1995. Corrected 16-IX-1996. Accepted 25-111-1997.)

Abstract: In Costa Rica, an annual outbreak of infant diarrheal disease (December and January) was reported since 1976, and rotavirus was incriminated 1ater as the main etiological agent (1976-1981). Apparently the disease has not been systematically studied in Costa Rica after 1981. For that reason the occurrence of the outbreak was retrospective1y documented for 1993-1995 and etiology was studied in 48 children treated for diarrhea at the Nacional Children Hospital (capital city of San Jose) during December, 1994 and January, 1995. Rotavirus (33%) and coronavirus (27%) were the main agents. To our knowledge, this is the first time that these viruses are incriminated in an outbreak of diarrhea.

Key words: Diarrhea, diarrheal disease outbreak, rotavirus, coronavirus.

Rotavirus, the main etiological agent of suspected as the cause of diarrheal outbreaks at infant diarrhea was described in 1973 (Bishop et the end and beginning of every year since that al. 1973, Flewett et al. 1973). Three years time. later, from December 1976 to January 1977, The aim of this research was the analysis of the frrst outbreakof diarrheal diseases asociated infectious agents associated with diarrhea in a with this virus was reported in Costa Rica group of children and a retrospective analysis of (Hemández et al. 1978). Then, other studies the monthly prevalence of diarrbeal diseases showed a profile of diarreal diseases in Costa treated at the Nacional Children Hospital, San Rican children with an important annual peak José, Costa Rica. from December to January or February, mainly associated with rotavirus (Mata et al. 1983). This annual outbreak of diarrheal disease MATERIAl.,s AND METHODS coincides with the worldwide prevalence of rotavirus (Christensen 1989), which has a We studied a group of 48 children with seasonal pattern: it is associated with winter or diarrhea. treated at that hospital between cooler months in warm regions (Christensen December, 1994 and January, 1995. A fecal 1989). sample from each was analyzed for parasites by To our knowledge, viral research of direct microscopy. Smears of fecal suspension diarrheal disease in Costa Rican children has were prepared, airdried, methanol fixed, stained not been systematically conducted after the by the cold Zield-Neelsen method, and analyzed 1976-1981 reports. Nevertheless, rotavirus is for the presence of Cryptosporidium spp. and 990 REVISTA DE BIOLOGIA TROPICAL

Campylobacter-like organisms. Bacteria were (33%) of rotavirus, and 13 (27%) of identified by inoculation in agar of coronavirus; seven of these children excreted MacConkey, SS, and Blaser. Futhermore, both víruses simultaneously. rotavrrusand coronavirus were studied by Dot­ The seriousness of viral diarrheas is ELISA using a monoclonal antibody against exemplified by the finding of 14 cases the VP6 of hllman rotavirus and a polyclonal dehydrated, three associated with virus,rota six antibody to calf coronavirus (Jiménez 1990). with coronavITus and five wíth both viruses, AdditionaUy, data of clínical symptoms were compared with 17 cases associated with other recorded for each parient. agents or without etiologic diagnosis (TabIe 1). A retrospective analysis of the prevalence of However, that difference was not statistically diarreal disease found at the hospital, was done significant (p=O.7); maybe because of the for the years 1993 - 1995. severity of ruarrhea: all these cases were_ hospitalized due to this disease. Moreover, vomit was present in 87% of the cases associated with viruses (p<0.5) and 32% of the RESULTS patients that excreted viruses showed respiratory symptoms (p<0.5, TabIe 1). The ínfectious agents were: One case each The annual profile of diarrheal diseases of Giardía, Ascans lubricoides, and showed a peak fromDecember to January (Fig. Campylobacter, two of Shigella sonney, 16 1).

TABLEl

Clinicalfindings in children with diarrhea associated with rotavirus and coronavirus

Clínica! signs Viral diarrheas The rest of the cases * Rotavirus Coronavirus Both virus Dehydrationl without dehydration 3/6 6/0 5/2 17/8 Days with diarrhea S; 3 / >3 6/3 5/1 6/0 19/7 Evacuationl24 hr $ 5 / >5 5/4 3/3 5/1 9/12 Vomitlwithout vomit 811 6/0 6/1 19/4 Respiratory symptomsl wi!hout 3/9 4/5 0/6 7/10

* The rest of the cases includes the cases without etiologic agent identified and !hose with bacteria. or parasites associated with diarrhea. Numbers to the left of vírglile refer to left condition in the "clínical signs" colnm and viceversa.

DISCUSSION

Data suggest that the annual outbreak of « UJ ¡: diarrhea is strongly associated with viral R;400 agents, at least « with rotavirus and coronavírus. Ci The formerwas incriminated previously in that u. 300 (.) outbreak (Hemández et al. 1977, 1980, Mata et � 200 al. 1977, 1983, Sirnhon et al. 1979, Odio et r/) .. al. 1980). This is the first u 100 time that coronavirus has been re1ated to that seasonal peak of diarrhea. It is possible that coronavITus might have been missed in previous research 1993 1994 1995 done in Costa Rica, because, samples observed under electron microscopy were clarified using genesolv, which could have destroyed this phospholipid enveloped virus. AdditionalIy, Fig 1. Monthly prevalence of diarrhea in children treated at fue National Children Hospital. San José, Costa Rica: many samples were analyzed only by ELISA there is an annual outbreak from December to the first using polyclonal antibodies to rotavirus. months of each year. Nevertheless, in an electron microscopy González el al.: Diarrhea in Costa Rica 991

econtrados. Hasta donde sabemos, esta es la primera vez research of viral diarrheas in calves, where the que esos dos virus son incriminados conjuntamente en la samples were not c1arified with geneso1v, both causalidad de un brote de diarrea. rotavirus and coronavirus were found with similar prevalence (Hernándezet al. 1987). The data presented herein cóncerning coronavirus REFERENCES were obtained with a Dot-ELISA using po1yclonal antibodies against a bovine strain, Bishop, R. F. G. P. Davidson, l. H. HohÍles & B. 1. Ruck. suggesting cross-reactivity between coronavirus 1973. Virus particles fu epithelial cells of duodenal strains from humans and calves. Neverthe1ess, mucosa from children with acute non-bacterial gastroentiritis.Lancet 2: 1228-1283. there may be different antigenic strains of Christensen, M. L. 1989. Human viral gastroenteritis. Clin. human enteric coronaviruses, because antigenic Microbiol. Rev. 2: 51-89. relatedness of the enteric human coronavirus Flewett, T. H. A. S. Bryden & H. Davis. 1973. Virus with other strains from respiratory infections particlesin gastroenteritis. Lancet 2: 1497. has been described (Germa et al. 1984); Germa, G. N. Passarani, P. M. Cereda & M. Battaglia. et converse1y, Mortesen al. (1985) did not find 1985. Antigenic relatedness of human enteric that cross reactivity. coronavirus strains to human coronavirus OC43: a The re1ationship between respiratory preliminary reporto J. Infect. Dis. 150: 618-619. symptoms and excretion of viruses (rotavirus Jiménez, C. 1990. Vergleichende Labordianostische Untersuechungen von Kotproben (EM. andlor coronavirus) in our patients was not Virusisolierung, inununologische Verfahren) zum statistically significant (p=0.08). However, Nachweis einer bovine Coronavirus infection bei coronavirus is re1ated with respiratory durchfallkranken Kalberm Veto Med. Diss, Justus­ Liebig- Universitat, Giessen, Gerrnany, 170 p. symptoms and with sporadic cases of diarrhea & in children (Christiensen 1989). Likewise, Hernández, F. L. Mata, C. Lizano E. Mohs. 1977. Prevalencia de rotavirus y descripción de una rotavirushas been incriminated with respiratory epidemiade diarrea por ese agente en Costa Rica. infections that precede the intestinal symptoms Acta Méd. Cost. 20: 297-304. (Zheng et al. 1991). Hence, the possib1e Hernández, F. L. Mata & V. H. Villalobos. 1980. Análisis involvement of respiratory tract in coronavirus electroforético del ácido ribonucleico de rotavirus de Costa Rica: Implicaciones epidemiológicas. Rev. and rotavirus infections cou1d explain the rapid Hosp. NaI. Niños 15: 21-30. spred of diarrhea! disease in hospitalized Hernández, F. R. M. Alvarez & M. T. Oviedo. 1987. children, as indeed occurs during the annual Epizotiología de las diarreas bovinas en Costa Rica. outbreak (Odio et al. 1980). Rev. Latinoamer.Microbiol. 29: 113-117. To OUT knowledge this is the first seasonal Mata, L. C. Lizano, F. Hernández, E. Mohs, L. Herrero, & 1. outbreak of child diarrhea simultaneously M. E. Peñaranda, F. Gamboa León. 1977. Agentes infecciosos en la diarrea del niño associated with coronavirus and rotavirus. hospitalizado. Bol. Méd. Hosp. Infant. 34: 955-969.

Mata, L. A. Sirnhon, R. Padilla, M. M. Gamboa, G. Vargas, F. Hernández, E. Mohs & C. Lizano. 1983. ACKNOWLEDGMENTS Diarrhea associated with rotaviruses, enterotoxigenic Eseheriehia eoli, Campylobaeter, and other agents in Costa Rican children, 1976-1981. Am. 1. Trop. Med. We thank Ferdinando Liprandi for providing Hyg. 32: 146-153. the Monoclonal Antibody to VP-6 of rotavirus. Mortesen,M. L. C. G. Ray, C. M. Payne, A. D. Friedman, This work was supported by Vicerrectoría 00 L. L. Minnich & C. Rousseau. 1985. Coronaviruslike Investigación, University of Costa Rica. particles in human gastrointestinal disease. Am. J. Dis. Child. 139: 928-934. Odio, C. F. Hernández, M. A. Ruiz, R. Padilla & E. Mohs. RESUMEN 1980. Rotavirus en un servicio de neonatología. Descripción de una epidemia Rev. Hosp. NaI. Niños En Costa Rica, entre 1976 y 1981 se documentó la 15: 159-172. ocurrencia de un brote anual (diciembre y enero) de & diarrea en niños, incriminando a rotavirus como el agente Sirnhon, A. S. Amato, F. Hernández, R. H. Yolken L. más importante. Pero hasta donde sabemos, la Mata. 1979. Diagnóstico de rotavirus por microscopia enfermedad no ha sido sistemáticamente investigada en electrónica y el ensayo iurnunosorbente enzima Costa Rica después de 1981. Por esa razón, se investigó la conjugada (ELISA). Bol.Of.Sanit.Panam. 86: 391-397. ocurrencia de tal brote retrospectivamente para los años Zheng, B. J. R. X. Chang, G. Z. Ma, 1. M. Xie, Q. Liu, X. 1993 a 1995 y se estudió la etiología en 48 niños con R. Liang & M. H. Ng. 1991. Rotavirus infections of diarrea atendidos en el Hospital Nacional de Niños entre the orophariynx and respiratory tract in young diciembre, 1994 y enero, 1995. Rotavirus (33%) y children. J. Med. Virol. 34: 29-37. coronavims (27%) fueron los principales agentes