Abstract

Coronaviruses are a group of related RNA viruses that cause diseases in mammals and birds. In humans, these viruses cause respiratory tract infections that can range from mild to lethal. Mild illnesses include some cases of the common cold (which is also caused by other viruses, predominantly rhinoviruses), while more lethal varieties can cause SARS, MERS, and COVID-19. Symptoms in other species vary: in chickens, they cause an upper respiratory tract disease, while in cows and pigs they cause diarrhea. There are as yet no vaccines or antiviral drugs to prevent or treat human coronavirus infections. Coronaviruses constitute the subfamily Orthocoronavirinae, in the family Coronaviridae, order Nidovirales, and realm Riboviria. They are enveloped viruses with a positive-sense single-stranded RNA genome and a nucleocapsid of helical symmetry. The genome size of coronaviruses ranges from approximately 26 to 32 kilobases, one of the largest among viruses. They have characteristic club-shaped spikes that project from their surface, which in electron micrographs create an image reminiscent of the solar corona, from which their name derives The name coronavirus is derived from Latin corona, meaning crown or wreath, itself a borrowing from Greek κορώνη korṓnē, garland, wreath. The name was coined by June Almeida and David Tyrrell who first observed and studied human coronaviruses. The word was first used in print in 1968 by an informal group of virologists in the journal Nature to designate the new family of viruses. The name refers to the characteristic appearance of virions (the infective form of the virus) by electron microscopy, which have a fringe of large, bulbous surface projections creating an image reminiscent of the solar corona or halo. This morphology is created by the viral spike peplomers, which are proteins on the surface of the virus. Coronaviruses were first discovered in the 1930s when an acute respiratory infection of domesticated chickens was shown to be caused by infectious bronchitis virus (IBV). Arthur Schalk and M.C. Hawn described in 1931 a new respiratory infection of chickens in North Dakota. The infection of new-born chicks was characterized by gasping and listlessness. The chicks mortality rate was 40–90%. Fred Beaudette and Charles Hudson(1998) six years later successfully isolated and cultivated the infectious bronchitis virus which caused the disease In the 1940s, two more animal coronaviruses, mouse hepatitis virus (MHV) and transmissible gastroenteritis virus (TGEV), were isolated.[17] It was not realized at the time that these three different viruses were related. Human coronaviruses were discovered in the 1960s. They were isolated using two different methods in the United Kingdom and the United States. E.C. Kendall, Malcolm Byone, and David Tyrrell working at the Common Cold Unit of the British Medical Research Council in 1960 isolated from a boy a novel common cold virus B814 The virus was not able to be cultivated using standard techniques which had successfully cultivated rhinoviruses, adenoviruses and other known common cold viruses. In 1965, Tyrrell and Byone successfully cultivated the novel virus by serially passing it through organ culture of human embryonic trachea. The new cultivating method was introduced to the lab by Bertil Hoorn. The isolated virus when intranasally inoculated into volunteers caused a cold and was inactivated by ether which indicated it had a lipid envelope. Around the same time, Dorothy Hamre and John Procknow at the University of Chicago isolated a novel cold virus 229E from medical students, which they grew in kidney tissue culture. The novel virus 229E, like the virus strain B814, when inoculated into volunteers caused a cold and was inactivated by ether.

Highlights

  • The study review in the related subjects is under investigation in order to highlight on the subject and provide framework for proper study

  • West Pokot, Baringo and Samburu appear to the safe zones but the reality could be different, leaders and experts warn

  • During the daily Covid-19 briefings on Monday, Health Chief Administrative Secretary Rashid Aman said while the government remains optimistic that the three regions will not record a coronavirus case, the reality is different

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Summary

Introduction

The study review in the related subjects is under investigation in order to highlight on the subject and provide framework for proper study. The residual functions are functions that are not defined as falling under the jurisdiction of either the national or the county government These are problematic and they need to be assigned to either level of government (whether by law or any other mechanism). County health services, including, in particular – county health facilities and pharmacies, ambulance services, promotion of primary health care, licensing and control of undertakings that sell food to the public, veterinary services (excluding regulation of the profession which is a national government function), cemeteries, funeral parlours and crematoria, and refuse removal, refuse dumps and solid waste disposal This is the sector which plays a great role in ensuring all health precautions is followed and adhered to at all cost. Following the re-organisation of Kenya's national administration, counties were integrated into a new national administration with the national government posting county commissioners to represent it at the counties.[ Establishment, County governments were established in 47 counties (largely based on the 1992 Districts of Kenya), after the scheduled general elections in March 2013

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