Coxsackie Viruses A and B - Case Study Example

COXSACKIE A AND B VIRAL INFECTION Introduction: Coxsackie Viruses A and B belong to the Picornaviradae family of viruses, because of they are small,icosahedral, single stranded, positive sense viruses, which are typical of this family. (Hendrickson, S.C., et al. 2006). The Coxsackie A and B viruses belong to the genus called enterovirus, a name that came about because of the presence of these viruses in the intestines. These viruses cause various illnesses such as pleurodynia, herpangina, aseptic meningitis, and neonatal myocarditis. (Cruickshank, R., et al. 1974). Investigations into the polio enterovirus in 1948, led to the discovery of the Coxsackie virus at Coxsackie, New York, and hence the name. Gilbert Dalldorf has been credited with the initial documentation of the Coxsakie virus. (Coxsackie A virus). There are twenty nine different kinds of Coxsackie virus identified so far, of which twenty three belong to the group A type of virus, and six to the group B type of virus. The Coxsackie viruses are divided into two groups called group A and group B depending on the type of lesions that they produce in suckling mice. (Coxsackie and Echoviruses). Diagnosis: Quite often diagnosis of Coxsackie A and B Viral infection is made on the basis of clinical presentation. However laboratory tests are also available that make use of samples of the blood, vesicles, and faeces. (Hewish, P., 2004). For laboratory diagnosis faecal samples or rectal swabs are used with more than one sample collected over interval periods of twenty-four hours to forty-eight hours. Isolation of the virus is also possible, especially where there are indications of respiratory infection, using throat swabs within five days from the onset of the symptoms. In the case of aseptic meningitis culture of the cerebro-spinal fluid is recommended. The best serological tests that are available for Coxsackie A and B viruses are neutralization, but they provide a difficulty in that these tests are labor intensive and time-taking with a minimum of seventy-two hours required for results to be available. PCR assays are becoming more and more popular in the detection and identification for all enteroviruses, especially when cerebro-spinal fluid is used for suspected cases of meningitis. (Coxsackie and Echoviruses). Etiology: The Coxsackie A virus group is considered to be the primary etiological agents responsible for herpangina and hand-foot-and-mouth disease (HFMD), while Coxsackie B virus group are considered responsible for epidemic pleurodynia or Bornholm disease, epidemic myalgia, myocarditis, pericarditis, and juvenile dermatomytosis. (Hendrickson, S.C., et al. 2006). The Coxsackie A and B viruses are also considered responsible for aseptic meningitis, encephalitis, paralysis, rash, fever, acute upper respiratory tract infection, enteritis and neonatal infections. Some of the other diseases for which the Coxsackie viruses could probably be the etiological agents are insulin dependent juvenile diabetes, pancreatitis, post-viral fatigue syndrome, and Reye’s syndrome. (Coxsackie and Echoviruses). Another worrying aspect with the Coxsackie A viral group is that a recent study has hpothesized that with the probability of the world being free of the polio virus, there is the possibility of the Coxsackie A viral group evolving into a new polio like virus. (Reider, E., et al. 2001). Morphology: As members of the Picornaviridae family, the Coxsackie A and B viruses are very small in size about 30 nm in diameter, and is a naked icosahedron. The genome is made up of a single-stranded monopartite RNA. Coxsackie viruses are found in the intestines, and demonstrate remarkable resistant characteristics to the harsh conditions of the intestine. (Libby, K., 2000). A recent study has suggested that the types of Coxsackie viruses vary with time rather than geographical locations. (Papa, A., et al., 2006). Epidemiology: The route of spread that is considered to be the most likely for Coxsackie And B virus is via the fecal oral route, and as such the chances of spread to family members is very high. To a lesser degree spread of the viral infection can occur from the focal lesions in the pharynx. The hot conditions of summer have been found to be conducive for the dissemination of the Coxsackie virus, and the large epidemics of Coxsackie viral infection have occurred in summer. Young children below the age of five are the main victims of Coxsackie viral infections, followed by young adults up to the age of twenty. Adults are seldom affected by Coxsackie viral infections. (Cruickshank, R., et al. 1974). The enterovirus group on the whole causes fifty million infections in America that lead to less than fifty thousand hospitalizations, with aseptic meningitis being the main cause for hospitalization. (Hendrickson, S.C., et al. 2006). Mode of Transmission and Portal of Entry: Access to the body for the Coxsackie virus is invariably through the mouth and the fecal oral route is the most likely mode of transmission. The Coxsackie virus could also be spread through contact with the mucosal secretions of an infected individual. The spread occurs through direct contact of contaminated surfaces or objects like a glass or telephone used by the infected individual. (What are Coxsakie B Virus?). Target Organs: The target organs include the skeletal muscles, brain, mouth, hand and feet, respiratory tract, heart, skin, genitalia, pancreas, lymphatic nodes, reticuloendothelial system organs, and eyes. (Hendrickson, S.C., et al. 2006). Progress of the Disease: The Coxsackie viruses demonstrate an incubation period of two to five days. Widespread outbreaks of disease are a distinct possibility, as the viruses are very contagious. Subsequent to ingestion of infected material, the Coxsackie viruses implant themselves in the alimentary tract, either the nasopharynx or the ileum or both, and replicate. The disease remains asymptomatic, in case the local replication is limited. Minor or nonspecific disease could develop when the viruses pass into the region lymphatic nodes and the reticuloendothelial system organs. The more severe infection with characteristically systemic infection occurs, when the virus spreads through the hematological route. The reaction of the body to an infection by Coxsackie viruses is through immune activation, and the production of immunoglobulin M (IgM)-type specific antibodies. These antibodies cause the rapid neutralization and elimination of the viruses from the blood stream and any other sites of infection. As such Coxsackie viruses are self- containing infections that last for a maximum of ten days. (Hendrickson, S.C., et al. 2006). Contraindications and Precautions: The symptoms of infection of Coxsackie viruses are similar to that of other viral infections like herpes and influenza, and this could lead to misdiagnosis. Coxsackie viruses that occur during the first trimester of pregnancy could cause spontaneous abortion. Complications of Myocarditis, Aseptic Meningitis, Meningoencephalitis, and paralysis are a possibility with Coxsackie viral infections. Deaths in neonates as a result of fulminant myocarditis have been seen. Good hygiene by pregnant women prior to and after delivery is the means to preventing infection in neonates. (Hendrickson, S.C., et al. 2006). Treatment: The focus of treatment is symptomatic, as anti-viral agents against Coxsackie viruses as such have not been developed. Antipyretics with sufficient hydration are the choice of treatment of fever caused due to Coxsackie viral infections. Mouth rinses with topical anesthetics are used to relieve pain in the case of mouth lesions due to Coxsackie infections. Allopurinol mouthwashes are employed for the quicker healing of mouthy lesions resulting from Coxsackie viral infections. The broad-spectrum antiviral drug Pleconaril is used in the treatment of severe Coxsackie infections like meningoencephalitis and neonatalviremia in patients with suppressed immunity systems. (Hendrickson, S.C., et al. 2006). Prevention: The normal preventive methods of vaccine and quarantine used against viral infections do not work with Coxsackie A and B viruses. The development of vaccines is impractical given the multiplicity of antigenic types, and in addition, normally the manifestation of the infection is mild. Quarantine has proved ineffective as a result of the high rate of infections that are not apparent. The only effective means at preventing Coxsackie A and B viral infections is maintenance of high standards of hygiene at the personal level, as well as the community level. (Coxsackie and Echoviruses). Literary References Coxsackie A virus. Retrieved July 24, 2006, from, WIKIPEDIA. The Free Encyclopedia. Web Site: http://en.wikipedia.org/wiki/Coxsackie_virus. Coxsackie and Echoviruses. Retrieved July 24, 2006, from, Web Site: http://virology-online.com/viruses/Enteroviruses5.htm. Cruickshank, R., et al. (1974). Medical Microbiology: Volume 1 Microbial Infections. Twelfth Edition. Great Britain. The English Language Book Society and Churchill Livingstone. Pp. 459-472 Hendrickson, S.C., et al. (2006). Enteroviral infections. Retrieved July 24, 2006, from, emedicine from WebMD. Web site: http://www.emedicine.com/derm/topic875.htm. Hewish, P. (2004). Coxsackie viruses. Retrieved July 24, 2006, from, PatientPlus. Web site: http://www.patient.co.uk/showdoc/40000343/. Libby, K. (2000). Coxsackie B 1-6. Retrieved July 24, 2006, from, Web Site: http://www.stanford.edu/group/virus/flavi/2000/coxsackieB.htm. Papa, A., et al. (2006). Genetic variation of coxsackie virus B5 strains associated with aseptic meningitis in Greece. Clinical microbiology and infection, 12(7), 688-691. Reider, E., et al. (2001). Will the polio niche remain vacant? Developments in biologicals, 105, 111-122. What are Coxsakie B Virus? Retrieved July 24, 2006, from, Web Site: http://www.safewater.org/facts/cox.htm. Read More