Outbreak investigation steps in the case of 2019 novel coronavirus infection, a review

Coronaviruses are a group of viruses that cause diseases in mammals and birds. In humans, the viruses cause respiratory infections which are typically mild including the common cold but other forms like Severe Acute Respiratory Syndrome (SARS), Middle East Respiratory Syndrome (MERS) and 2019 novel coronaviruses can be lethal. In cows and pigs they may cause diarrhea, while in chickens they can cause an upper respiratory disease [1,2].

responsible for severe profuse enteritis of young calves, Feline Coronavirus (FCoV) causes mild enteritis in cats as well as severe Feline infectious peritonitis (other variants of the same virus), the two types of canine coronavirus (CCoV) (one causing enteritis, the other found in respiratory diseases), Turkey Coronavirus (TCV) causes enteritis in turkeys, Ferret enteric coronavirus causes epizootic catarrhal enteritis in ferrets, Ferret systemic coronavirus causes FIP-like systemic syndrome in ferrets. Pantropic canine coronavirus, Rabbit enteric coronavirus causes acute gastrointestinal disease and diarrhea in young European rabbits. Mortality rates are high [2,5].
A coronavirus is a kind of common virus that causes an infection in the nose, sinuses, or upper throat. Most coronaviruses are not dangerous. Some types of coronaviruses are serious, though. About 858 people have died from Middle East Respiratory Syndrome (MERS), which fi rst appeared in 2012 in Saudi Arabia and then in other countries in the Middle East, Africa, Asia, and Europe. In April 2014, the fi rst American was hospitalized for MERS in Indiana and another case was reported in Florida. Both had just returned from Saudi Arabia. In May 2015, there was an outbreak of MERS in Korea, which was the largest outbreak outside of the Arabian Peninsula. In 2003, 774 people died from a Severe acute Respiratory Syndrome (SARS) outbreak. As of 2015, there were no further reports of cases of SARS [6][7][8].

Novel coronavirus infection
In December 31/2019, a pneumonia outbreak was reported in Wuhan, China, the outbreak was traced to a novel strain of coronavirus which was labeled as 2019-nCoV by the World Health Organization [4].
As of 30 January 2020 (16:00 UTC), the number of deaths was 214 and more than 8,230 confi rmed cases in this coronavirus pneumonia outbreak. The Wuhan strain has been identifi ed as a new strain of Beta-coronavirus from group 2B with a ~70% genetic similarity to the SARS-CoV. The virus was suspected to have originated in snakes but many leading researchers disagree with this conclusion. Daniel Lucey, an infectious disease specialist at Georgetown University, stated that "Now it seems clear that seafood market is not the only origin of the virus" [4,10].
In other animals, Coronaviruses have been recognized as causing pathological conditions in different domesticated animals since the early 1970s. Except for avian infectious bronchitis, the major related diseases have mainly an intestinal location. Coronaviruses primarily infect the upper respiratory and gastrointestinal tract of mammals and birds.
They also cause a range of diseases in farm animals and domesticated pets, some of which can be serious and are a threat to the farming industry. In chickens, the Infectious Bronchitis Virus (IBV), a coronavirus, targets not only the respiratory tract but also the urogenital tract [11].     Citation: Alene

Routes of transmission
Most coronaviruses spread the same way as other cold-causing viruses do: through infected people coughing and sneezing, by touching an infected person's hands or face, or by touching things such as doorknobs that infected people have touched.
Human coronaviruses most commonly spread from an infected person to others through: Respiratory droplets released into the air by coughing and sneezing; Close personal contact, such as touching or shaking hands; Touching an object or surface with the virus on it, then touching your mouth, nose, or eyes before washing your hands; and Rarely, fecal contamination [14].
When person-to-person spread has occurred with 2019 Novel coronavirus, MERS and SARS, it is thought to have happened mainly via respiratory droplets produced when an infected person coughs or sneezes, similar to how infl uenza and other respiratory pathogens spread. Spread of SARS and MERS between people has generally occurred between close contacts [4].

Clinical symptoms
The symptoms of most coronaviruses are similar to any other upper respiratory infection, including runny or stuffy nose, coughing, sore throat, and sometimes a fever. In most cases, people won't know whether they have a coronavirus or a different cold-causing virus, such as rhinovirus. According to different reports, patients present with: fever, elevated body temperature, dry cough, fatigue or muscle pain, breathing diffi culties. Less common symptoms of coronavirus include: coughing up mucus or blood, headaches, diarrhea but as the disease progresses, patients also come down with pneumonia, which infl ames the lungs and causes them to fi ll with fl uid. This can be detected by an X-ray and was present in all 41 cases studied [13,15].

Investigation of novel coronavirus (2019-ncov) outbreak
In epidemiology, an outbreak is a sudden increase in occurrences of a disease in a particular time and place. It may affect a small and localized group or impact upon thousands of animal and/or people across an entire continent. Four linked cases of a rare infectious disease may be suffi cient to constitute an outbreak. Outbreaks include epidemics, which term is normally only used for infectious diseases, as well as diseases with an environmental origin, such as a water or foodborne disease. They may affect a region in a country or a group of countries. Pandemics are near-global disease outbreaks. Outbreak legislation is still in its infancy and not many countries have had a direct and complete set of the provisions. However, some countries do manage the outbreaks using relevant acts, such as public health law [16]. Generally the new 2019 novel coronavirus outbreak in many countries especially in China can be investigated by the following steps.

Descriptive data collection and analysis
The 2019 novel coronavirus outbreak occurred fi rstly in Wuhan province, China which has a fl uctuating agro ecological climatic condition and high population density. The data collection for identifi cation, confi rmation and investigation of the 2019 nCoV, is based on temporal and special epidemiological and clinical considerations as follow; any person with travelhistory to Wuhan city, China in the 14 days before the onset of illness (or) any person being in close contact with a laboratoryconfi rmed case of 2019-nCoV in the 14 days before the onset of illness and any person with clinical symptoms compatible with severe acute respiratory infection seeking healthcare or admitted to hospital with clinical or radiological evidence of pneumonia (or) any person with fever or recent history of fever (>38°C) and acute respiratory infection (sudden onset of respiratory infection with one or more of the following symptoms: shortness of breath, cough or sore throat) [19].

Hypothesis generation
The 2019 novel coronavirus infection out break affects both animals and humans but it severely affects human and the symptoms manifested by infected individual slightly varies between person to person but it becomes more severe in the people with weak immunity, elder or of young age. The disease occurs in the areas where population density is very high in whole selling markets of live animal, seafood and transportation areas. Its incubation period is between 2 to 14 days, but there is evidence that it may still be contagious during this period and possibly for several days after recovery.
Symptoms include fever, coughing and breathing diffi culties, and it can be fatal [20].
Most often, spread from person-to-person happens among close contacts (about 6 feet). Person-to-person spread is thought to occur mainly via respiratory droplets produced when an infected person coughs or sneezes, similar to how infl uenza and other respiratory pathogens spread. These droplets can land in the mouths or noses of people who are nearby or possibly be inhaled into the lungs. It's currently unclear if a person can get 2019-nCoV by touching a surface or object that has the virus on it and then touching their own mouth, nose, or possibly their eyes [21].

Control measures and recommendations
Public Health Measures: Once the outbreak was reported, routine coronavirus-control measures were instituted. After fi ndings suggesting possible involvement of SARS-CoV were reported, these measures were enhanced, and fl u and SARStype respiratory and contact precautions were exercised around symptomatic cases [13].
The best way to prevent infection is to take precautions to avoid exposure to this virus, which are similar to the precautions you take to avoid the fl u. Center for communicable disease control always recommends these everyday actions to help prevent the spread of respiratory viruses, including: Wash your hands often with soap and water for at least 20 seconds, if soap and water are not available, use an alcohol-based hand sanitizer, avoid touching your eyes, nose, and mouth with unwashed hands, avoid close contact with people who are sick, stay home when you are sick, Cover your cough or sneeze with a tissue, then throw the tissue in the trash, clean and disinfect frequently touched objects and surfaces [20].

Management and vaccination
The main treatment strategy for typical corona virus infection is supportive therapy, in deeding administration of antipyretics and analgesics, maintenance of hydration, respiratory support by either mechanical ventilation or extracorporeal Membrane Oxygenation (ECMO), and treatment with antibiotics in the case of bacterial super infections. However, such treatments may not be suffi cient for 2019-nCoV and MERS-CoV infections, which may be more severe. Ribavirin and interferon alpha have been shown to have synergistic effects and are more benefi cial when started early. Additionally, mycophenolic acid has been shown to be effi cacious and can be used as a mono therapy; however, initial clinical trials included few patients, and further studies are necessary. There is currently no vaccine to prevent 2019-nCoV infection. In January 2020, several organizations and institutions began work on creating vaccines for 2019 n-CoV based on the published genome. Although several companies are attempting to develop 2019-nCoV SARS-CoV and MERS-CoV vaccines, none are available yet. Improving our under-standing of viral antibodies will facilitate the design of appropriate and effi cacious vaccines [11].

Protection and surveillance zones
The geographical delimitation of those two zones must take into account; the administrative borders and natural barriers, where will be taken the surveillance and control measures that can stop animal disease virus spreading. Protection zone will have a radius of a minimum 3 kilometers, having the center into outbreak, and the surveillance zone will have a radius of a minimum 10 kilometers, having the same center. These two zones will be at least of 3 and 10. kilometers, but they might be enlarged, not necessary as a circle, but as any other geometrical form, varying with natural barriers and the administrative border [9,24].
Developed interim guidance for laboratory diagnosis, clinical management, infection prevention and control in health care settings, home care for patients with suspected novel corona virus, risk communication and community engagement. Prepared disease commodity package for supplies necessary in identifi cation and management of confi rmed patients; Provided recommendations to reduce risk of transmission from animals to humans; Providing guidance on early investigations, The fi rst protocol that is available is; a household transmission investigation protocol for 2019-novel coronavirus (2019-nCoV) infection [4,25].

Coronavirus in Ethiopia
January 28/2020 in the wake of the coronavirus outbreak currently enduring in Wuhan China, Ethiopia isolated four suspected cases in isolation that arrived at the Bole Airport from China. Samples were taken from these four suspected cases in isolation and medical samples were sent to South Africa for further test. Coronavirus has been detected in Ethiopia yet. However, all the samples were tested and the preliminary results showed negative with no positive case of the virus so far. Ethiopia still has no coronavirus positive case, she noted adding that the country will step up its surveillance and testing facilities to ensure that it can manage to provide immediate health care response [20,21] Ethiopia has heightened preparedness to prevent the entry and spread of the coronavirus to the country. The State Minister underscored that adequate preparations are in place, particularly at the Bole International Airport for thermal screening, preliminary surveillance, and testing of arrivals from China and its neighboring countries. The Ethiopian Public Health Institute (EPHI) leads and coordinates national preparedness activities through a national Technical Working Group (TWG). The TWG, which meets several times a week to devise plans, monitor progress, develop guidelines and standard operating procedures, oversee logistics and strengthen surveillance at the Addis Ababa Bole International Airport [9,16].

Conclusion and recommendations
The outbreak of coronavirus that began in China and spread across the world, leaving more than around fi ve hundred (493 deaths) people dead and 24623 confi rmed cases until February 5/ 2020, has raised alarm about the ability of countries to handle an epidemic or pandemic. The recent Global Health Security Index gives insights into which of 195 nations including Ethiopia are ready to fi ght a major health emergency that could wreak havoc on the global economy.  Rapid response to and mitigation of the spread of an epidemic;  Suffi cient and robust health system to treat the sick and protect health workers;  Proper collection, submission and laboratory analysis of probable and suspected cases by using current and updated serological and molecular investigation techniques.