Basic protective measures against the new coronavirus

Stay aware of the latest information on the COVID-19 outbreak, available on the WHO website and through your national and local public health authority. Most people who become infected experience mild illness and recover, but it can be more severe for others. Take care of your health and protect others by doing the following:

Wash your hands frequently

Regularly and thoroughly clean your hands with an alcohol-based hand rub or wash them with soap and water.

Why? Washing your hands with soap and water or using alcohol-based hand rub kills viruses that may be on your hands.

Maintain social distancing

Maintain at least 1 metre (3 feet) distance between yourself and anyone who is coughing or sneezing.

Why? When someone coughs or sneezes they spray small liquid droplets from their nose or mouth which may contain virus. If you are too close, you can breathe in the droplets, including the COVID-19 virus if the person coughing has the disease.

Avoid touching eyes, nose and mouth

Why? Hands touch many surfaces and can pick up viruses. Once contaminated, hands can transfer the virus to your eyes, nose or mouth. From there, the virus can enter your body and can make you sick.

Practice respiratory hygiene

Make sure you, and the people around you, follow good respiratory hygiene. This means covering your mouth and nose with your bent elbow or tissue when you cough or sneeze. Then dispose of the used tissue immediately.

Why? Droplets spread virus. By following good respiratory hygiene you protect the people around you from viruses such as cold, flu and COVID-19.

If you have fever, cough and difficulty breathing, seek medical care early

Stay home if you feel unwell. If you have a fever, cough and difficulty breathing, seek medical attention and call in advance. Follow the directions of your local health authority.

Why? National and local authorities will have the most up to date information on the situation in your area. Calling in advance will allow your health care provider to quickly direct you to the right health facility. This will also protect you and help prevent spread of viruses and other infections.

Stay informed and follow advice given by your healthcare provider

Stay informed on the latest developments about COVID-19. Follow advice given by your healthcare provider, your national and local public health authority or your employer on how to protect yourself and others from COVID-19.

Why? National and local authorities will have the most up to date information on whether COVID-19 is spreading in your area. They are best placed to advise on what people in your area should be doing to protect themselves.

Protection measures for persons who are in or have recently visited (past 14 days) areas where COVID-19 is spreading

• Follow the guidance outlined above.

• Stay at home if you begin to feel unwell, even with mild symptoms such as headache and slight runny nose, until you recover. Why? Avoiding contact with others and visits to medical facilities will allow these facilities to operate more effectively and help protect you and others from possible COVID-19 and other viruses.

• If you develop fever, cough and difficulty breathing, seek medical advice promptly as this may be due to a respiratory infection or other serious condition. Call in advance and tell your provider of any recent travel or contact with travelers. Why? Calling in advance will allow your health care provider to quickly direct you to the right health facility. This will also help to prevent possible spread of COVID-19 and other viruses.

Preventing the Spread of Infectious Diseases coronavirus

Preventing the Spread of Infectious Diseases

Decrease your risk of infecting yourself or others:.
Written by vinod Kumar kushwaha
                      Msc microbiogist

• Wash your hands often. This is especially important before and after preparing food, before eating and after using the toilet.
• Get vaccinated. Immunization can drastically reduce your chances of contracting many diseases. Keep your recommended vaccinations up-to-date.
• Use antibiotics sensibly. Take antibiotics only when prescribed. Unless otherwise directed, or unless you are allergic to them, take all prescribed doses of your antibiotic, even if you begin to feel better before you have completed the medication.
• Stay at home if you have signs and symptoms of an infection.Don't go to work or class if you're vomiting, have diarrhea or are running a fever.
• Be smart about food preparation. Keep counters and other kitchen surfaces clean when preparing meals. In addition, promptly refrigerate leftovers. Don't let cooked foods remain at room temperature for an extended period of time.
• Disinfect the 'hot zones' in your residence. These include the kitchen and bathroom — two rooms that can have a high concentration of bacteria and other infectious agents.
• Practice safer sex. Use condoms. Get tested for sexually transmitted diseases (STDs), and have your partner get tested— or, abstain altogether.
• Don't share personal items.Use your own toothbrush, comb or razor blade. Avoid sharing drinking glasses or dining utensils.
• Travel wisely. Don't fly when you're ill. With so many people confined to such a small area, you may infect other passengers in the plane. And your trip won't be comfortable, either. Depending on where your travels take you, talk to your doctor about any special immunizations you may need.

What is coronavirus, how does Covid-19 spread and what are the symptoms?

Written by:: 
vinod Kumar kushwaha 
       Msc Microbiologist
16/3/20




CORONAVIRUS has killed more than 3,400 people to date and infected at least 100,000 others.

But what is coronavirus, how does it spread and what are the disease symptoms?

What is coronavirus?

Coronaviruses are a large family of viruses that can cause infections ranging from the common cold to Severe Acute Respiratory Syndrome (Sars).

The virus attacks the respiratory system, causing pneumonia-like lung lesions.

Some of the virus types cause less serious disease, while others – like the one that caused Middle East Respiratory Syndrome (Mers) – are far more severe.

In 2003 an outbreak of a similar virus, Sars, killed more than 900 around the world within weeks.

What are the symptoms?

Symptoms are similar to a common cold.

They include:

• a runny nose
• headache
• cough
• fever
• shortness of breath
• chills
• body aches

In most cases, you won’t know whether you have a coronavirus or a different cold-causing virus, such as rhinovirus.

But if a coronavirus infection spreads to the lower respiratory tract (your windpipe and your lungs), it can cause pneumonia, especially in older people, people with heart disease or those with weakened immune systems.

There is currently no vaccine for coronavirus

To help prevent infection, do the same things you do to avoid the common cold such as using alcohol-based anti-bacterial soaps and sprays.

People should also avoid touching their eyes, nose and mouth – and avoid contact with people who are infected.

A coronavirus infection should be treated the same way a cold is treated.

Biting your nails can seriously increase your risk of contracting coronavirus, according to an allergy and infectious diseases specialist.

Here’s what can you do to keep your home safe.

How does coronavirus spread?

Coronavirus is an airborne virus, spread in a similar way to colds and the flu.

It is incredibly contagious and is spread through contact with anything the virus is on as well as infected breath, coughs or sneezes.

This means that anyone who is infected can pass it on to any surface or person they breathe on or touch.

How far has the virus spread so far?

In spite of efforts to contain the virus, it has gone international.

China, Japan, Thailand, Singapore, Hong Kong, South Korea, Australia, Taiwan, Malaysia, US, Germany, Vietnam, Macao, France, UAE, Canada, Italy, UK, India, Philippines, Russia, Nepal, Cambodia, Finland, Nepal, Sri Lanka, Belgium and Sweden have all reported cases.

• January 31, 2020, the first two cases were reported in the UK.
• February 6, a third Brit tested positive for coronavirus.
• February 8, five Britons, including one child, were diagnosed with the virus in France  after coming into contact with a person who had been in Singapore.
• February 10, it was revealed there were eight cases in the UK.
• February 12, the first case in London was confirmed bringing the total in UK to nine.
• February 16, the eight-month-old baby feared to be Britain’s youngest coronavirus victim given all
• 
  
• How many people have died from coronavirus?

The global death toll stands at over 3,400.

In China, the majority of deaths have been in the central province of Hubei.

चीन से निकलकर पुरी दुनिया को चपेट में लेने वाले करोना वायरस की दास्तां एक नज़र विशेष करोना वायरस पर

कोरोना को लेकर पिछले 2 महीने से चीन में और अब पूरी दुनिया में हाहाकार मचा हुआ है. ईरान से लेकर इटली तक और इंग्लैंड से लेकर अमेरिका तक और अब तो भारत में भी कोरोना दाखिल हो चुका है. चीन से निकले इस जानलेवा वायरस का जिस तरह अभी तक इलाज नहीं मिला है उसी तरह इस वायरस के रहस्य को भी अभी तक सुलझाया नहीं जा सका है. लिहाज़ा इस वायरस की तह तक पहुंचना बेहद ज़रूरी है. ये जानना जरूरी है कि कोरोना आखिर कब, कैसे, क्यों और कहां से आया?

जनवरी 2019, इंस्टिट्यूट ऑफ वायरलॉजी नेशनल बायोसेफ्टी लैब. वुहान, चीन

चीन की वुहान लैब में इबोला, निपाह, सॉर्स और दूसरे घातक वायरसों पर रीसर्च कर रहे वैज्ञानिक अपने माइक्रोस्कोप में एक अजीब सा वायरस नोटिस कर रहे थे. मेडिकल हिस्ट्री में ऐसा वायरस पहले कभी नहीं देखा गया था. इसके जेनेटिक सिक्वेंस को गौर से देखने पर पता चल रहा था कि ये चमगादड़ के करीबी हो सकते हैं. वैज्ञानिक हैरान थे क्योंकि इस वायरस में वो सार्स वायरस के साथ समानता को देख पा रहे थे. जिसने 2002-2003 में चीन में महामारी ला दी थी और दुनिया भर में 700 से ज़्यादा लोग मारे गए थे. उस वक्त भी ये बताया गया था कि सार्स छूने और संक्रमित व्यक्ति के छींकने या खांसने से फैलता है. लेकिन तब चीन इस वायरस को छुपा ले गया था.

दिसंबर का पहला हफ्ता 2019, वुहान, चीन

दिसंबर के शुरुआती हफ्ते में वुहान की सी-फूड मार्केट के ईर्द-गिर्द रहने वाले कई लोग बुखार से पीड़ित होने शुरु हो गए. इनके टेस्ट के लिए सैंपल लैब में भेजे गए. जिसके बाद ये सैंपल वुहान इंस्टिट्यूट ऑफ वायरलॉजी नेशनल बायोसेफ्टी लैब के पास पहुंचे. यहां वैज्ञानिक के माइक्रोस्कोप जो उन्हें दिखा रहे थे. वो आने वाले जानलेवा ग्लोबल खतरे का संकेत था. मगर चीनी अधिकारियों ने डॉक्टरों और वैज्ञानिकों को बदनामी और अफरातफरी के माहौल से बचने के लिए खामोश करा दिया.

दिसंबर का आखिरी हफ्ता 2019, वुहान, चीन

डॉ. ली वेनलियांग के अस्पताल में स्थानीय सी-फूड मार्केट से करीब सात मरीज़ पहुंचे. ये वही डॉ ली वेनलियांग थे, जिन्होंने दुनिया को पहली बार इस जानलेवा वायरस से आगाह कराया था. बहरहाल इन मरीज़ों के लक्षण देखकर ही डॉ ली को समझ में आ गया कि ये सभी के सभी किसी अनजान घातक वायरस के शिकार हो गए हैं. उन्होंने फौरन इस बीमारी के बारे में दूसरे डॉक्टरों को अलर्ट किया. और इस वायरस के बारे में अपनी रिपोर्ट दी. इतना ही नहीं इस बारे में उन्होंने वीचैट एप पर अपने मेडिकल कॉलेज के एलुमनी ग्रुप में भी जानकारी दी. और सबको अपने जानकारों, दोस्तों और रिश्तेदारों को इस बारे में आगाह करने को कहा लेकिन कुछ ही घंटों में उनके मैसज का स्क्रीनशॉट वायरल हो गया.

जनवरी का पहला हफ्ता 2020, वुहान, चीन

नए साल के जश्न में दुनिया और चीन डूबे थे. और ठीक उनकी नाक के नीचे ये वायरस लगातार फैलता जा रहा था. 7 से 14, 14 से 21, 21 से 42 होते. ये तादाद हज़ार तक जा पहुंच गई. मगर चीन इस पर रोकथाम के बजाए. इस जानलेवा बीमारी को दुनिया से छुपाने में ही लगा रहा.

25 जनवरी 2020, इंस्टिट्यूट ऑफ वायरलॉजी नेशनल बायोसेफ्टी लैब, वुहान, चीन

अंग्रेज़ी नए साल के बाद आया चीनी नया साल. अफरातफरी से बचने के लिए चीन ने इस जानलेवा वायरस की खबर को सामने तो नहीं आने दिया. मगर अंदर ही अंदर वुहान के इंस्टिट्यूट ऑफ वायरलॉजी नेशनल बायोसेफ्टी लैब में इसकी जांच चलने लगी. यूं भी इस लैब में पिछले कई सालों से चमगादड़ों से फैलने वाली बीमारियों पर रिसर्च चल रही थी. ये रिसर्च इसलिए थी क्योंकि ना सिर्फ वुहान और आसपास के इलाकों में चमगादड़ों की तादाद ज़्यादा है. बल्कि यहां चमगादड़ों और दूसरे तमाम जानवरों का मांस खाने और सूप पीने का चलन भी ज़ोरों पर था. और अब तक की जांच में ये तो साफ हो रहा था कि हो ना हो ये जानलेवा वायरस इन्हीं चमगादड़ों से ही फैला है. चाइनीज सेंटर फॉर डिज़ीज़ कंट्रोल एंड प्रिवेशन की स्टडी के डेटा भी इसी तरफ इशारा कर रहे थे.

फरवरी का पहला हफ्ता 2020, वुहान, चीन

डॉ. ली वेनलियांग इस बीच लगातार अपने डॉक्टर साथियों और लोगों को इस जानलेवा वायरस से ना सिर्फ आगाह कर रहे थे. बल्कि पीड़ितों को आइसोलेशन वार्ड में रखकर अपने तौर पर इलाज भी कर रहे थे. इस बीच ये खबरें चीन से निकलकर दुनिया तक पहुंचने लगी. चीन ने भी अब तक मान लिया कि उसके मुल्क को कोरोना नाम की एक महामारी ने जकड़ लिया है. वहीं दूसरी तरफ चीनी सरकार ने 34 साल के डॉक्टर ली के वायरल हो चुके कोरोना वायरस से आगाह करने वाले मैसेज का संज्ञान लेते हुए. नोटिस भेजकर जवाब मांगा. मगर डाक्टर ली की परेशानियां यहीं खत्म नहीं हुईं. इसके फौरन बाद उनपर अफवाह फैलाने का आरोप लगा दिया गया और उन्हें लिखित में मांफी मांगनी पड़ी. इस बीच वुहान और आसपास के इलाकों के साथ साथ पूरा चीन इस जानलेवा वायरस की चपेट में आ चुका था. और उससे होने वाली मौतों का आंकड़ा लगातार बढ़ता जा रहा था.

7 फरवरी 2020, वुहान, चीन

अचानक खबर आई की कोरोना वायरस के बारे में सबसे पहले जानकारी देने वाले डॉक्टर ली की मौत हो गई है. बताया गया कि डॉक्टर ली 12 जनवरी से अस्पताल में भर्ती थे. और 30 जनवरी को पता चला कि वो कोरोना वायरस की चपेट में आ चुके हैं. चीन ने कहा कि उन्हें बचाने की कोशिश हुई. लेकिन बचाया नहीं जा सका. वुहान सेंट्रल हॉस्पिटल ने अपनी रिपोर्ट में कहा कि डॉ ली की मौत 7 फरवरी की. रात करीब 2 बजकर 58 मिनट पर हुई. बताया गया कि उन्हें कफ और बुखार था. हालांकि सरकार विरोधी गुटों का ये मानना था कि चीन ने उन्हें इस महामारी का खुलासा करने की सज़ा दी है.

मरीजों को मारने की अर्जी!

ये खबर इसलिए भी हावी हुई क्योंकि शुरुआत में चीन के 20 हज़ार कोरोना पीड़ितों को मार देने के लिए सुप्रीम पीपुल्स कोर्ट में अर्जी देने वाली खबर भी आई थी. मगर ये दोनों ही खबरें कंफर्म नहीं हो सकी. लेकिन चीन में जो कंफर्म हुआ. वो था दुनिया में अबतक का सबसे जानलेवा वायरस के सामने आने का सच. जो अब तक देखते देखते ही हज़ारों लोगों को अपनी चपेट में लेकर बेमौत मार चुका था.

New chapter of Microbiology book Corona virus structure of Corona virus prevention epidemiology pathogenesis

General Concepts

Clinical Presentation

Coronaviruses cause acute, mild upper respiratory infection (common cold).

Structure

Spherical or pleomorphic enveloped particles containing single-stranded (positive-sense) RNA associated with a nucleoprotein within a capsid comprised of matrix protein. The envelope bears club-shaped glycoprotein projections.

Classification

Coronaviruses (and toroviruses) are classified together on the basis of the crown or halo-like appearance of the envelope glycoproteins, and on characteristic features of chemistry and replication. Most human coronaviruses fall into one of two serotypes: OC43-like and 229E-like.

Multiplication

The virus enters the host cell, and the uncoated genome is transcribed and translated. The mRNAs form a unique “nested set” sharing a common 3′ end. New virions form by budding from host cell membranes.

Pathogenesis

Transmission is usually via airborne droplets to the nasal mucosa. Virus replicates locally in cells of the ciliated epithelium, causing cell damage and inflammation.

Host Defenses

The appearance of antibody in serum and nasal secretions is followed by resolution of the infection. Immunity wanes within a year or two.

Epidemiology

Incidence peaks in the winter, taking the form of local epidemics lasting a few weeks or months. The same serotype may return to an area after several years.

Diagnosis

Colds caused by coronaviruses cannot be distinguished clinically from other colds in any one individual. Laboratory diagnosis may be made on the basis of antibody titers in paired sera. The virus is difficult to isolate. Nucleic acid hybridization tests (including PCR) are now being introduced.

Control

Treatment of common colds is symptomatic; no vaccines or specific drugs are available. Hygiene measures reduce the rate of transmission.

Introduction

Coronaviruses are found in avian and mammalian species. They resemble each other in morphology and chemical structure: for example, the coronaviruses of humans and cattle are antigenically related. There is no evidence, however, that human coronaviruses can be transmitted by animals. In animals, various coronaviruses invade many different tissues and cause a variety of diseases, but in humans they are only proved to cause mild upper respiratory infections, i.e. common colds. On rare occasions, gastrointestinal coronavirus infection has been associated with outbreaks of diarrhoea in children, but these enteric viruses are not well characterized and are not discussed in this chapter.

Clinical Manifestations

Coronaviruses invade the respiratory tract via the nose. After an incubation period of about 3 days, they cause the symptoms of a common cold, including nasal obstruction, sneezing, runny nose, and occasionally cough (Figs. 60-1and 60-2). The disease resolves in a few days, during which virus is shed in nasal secretions. There is some evidence that the respiratory coronaviruses can cause disease of the lower airways but it is unlikely that this is due to direct invasion. Other manifestations of disease such as multiple sclerosis have been attributed to these viruses but the evidence is not clear-cut.

Structure

Coronavirus virions are spherical to pleomorphic enveloped particles (Fig. 60-3). The envelope is studded with projecting glycoproteins, and surrounds a core consisting of matrix protein enclosed within which is a single strand of positive-sense RNA (Mr 6 × 106) associated with nucleoprotein. The envelope glycoproteins are responsible for attachment to the host cell and also carry the main antigenic epitopes, particularly the epitopes recognized by neutralizing antibodies. OC43 also possesses a haemagglutan

Classification and Antigenic Types

The coronaviruses were originally grouped into the family Coronaviridae on the basis of the crown or halo-like appearance given by the glycoprotein-studded envelope on electron microscopy. This classification has since been confirmed by unique features of the chemistry and replication of these viruses. Most human coronaviruses fall into one of two groups: 229E-like and OC43-like. These differ in both antigenic determinants and culturing requirements: 229E-like coronaviruses can usually be isolated in human embryonic fibroblast cultures; OC43-like viruses can be isolated, or adapted to growth, in suckling mouse brain. There is little antigenic cross-reaction between these two types. They cause independent epidemics of indistinguishable disease.

Multiplication

It is thought that human coronaviruses enter cells, predominantly, by specific receptors. Aminopeptidase-N and a sialic acid-containing receptor have been identified to act in such a role for 229E and OC43 respectively. After the virus enters the host cell and uncoats, the genome is transcribed and then translated. A unique feature of replication is that all the mRNAs form a “nested set” with common 3′ ends; only the unique portions of the 5′ ends are translated. There are 7 mRNAs produced. The shortest mRNA codes for the nucleoprotein, and the others each direct the synthesis of a further segment of the genome. The proteins are assembled at the cell membrane and genomic RNA is incorporated as the mature particle forms by budding from internal cell membranes.

Pathogenesis

Studies in both organ cultures and human volunteers show that coronaviruses are extremely fastidious and grow only in differentiated respiratory epithelial cells. Infected cells become vacuolated, show damaged cilia, and may form syncytia. Cell damage triggers the production of inflammatory mediators, which increase nasal secretion and cause local inflammation and swelling. These responses in turn stimulate sneezing, obstruct the airway, and raise the temperature of the mucosa.

Host Defenses

Although mucociliary activity is designed to clear the airways of particulate material, coronaviruses can successfully infect the superficial cells of the ciliated epithelium. Only about one-third to one-half of infected individuals develop symptoms, however. Interferon can protect against infection, but its importance is not known. Because coronavirus infections are common, many individuals have specific antibodies in their nasal secretions, and these antibodies can protect against infection. Most of these antibodies are directed against the surface projections and neutralize the infectivity of the virus. Cell-mediated immunity and allergy have been little studied, but may play a role.

Epidemiology

The epidemiology of coronavirus colds has been little studied. Waves of infection pass through communities during the winter months, and often cause small outbreaks in families, schools, etc. (Fig. 60-2). Immunity does not persist, and subjects may be re-infected, sometimes within a year. The pattern thus differs from that of rhinovirus infections, which peak in the fall and spring and generally elicit long-lasting immunity. About one in five colds is due to coronaviruses.

The rate of transmission of coronavirus infections has not been studied in detail. The virus is usually transmitted via inhalation of contaminated droplets, but it may also be transmitted by the hands to the mucosa of the nose or eyes.

Diagnosis

There is no reliable clinical method to distinguish coronavirus colds from colds caused by rhinoviruses or less common agents. For research purposes, virus can be cultured from nasal swabs or washings by inoculating organ cultures of human fetal or nasal tracheal epithelium. The virus in these cultures is detected by electron microscopy or other methods. The most useful method for laboratory diagnosis is to collect paired sera (from the acute and convalescent phases of the disease) and to test by ELISA for a rise in antibodies against OC43 and 229E. Complement fixation tests are insensitive; other tests are inconvenient and can be used only for one serotype. Direct hybridization and polymerase chain reaction tests for viral nucleic acid have been developed and, particularly with the latter, are the most sensitive assays currently available for detecting virus .

Control

Although antiviral therapy has been attempted, the treatment of coronavirus colds remains symptomatic. The likelihood of transmission can be reduced by practising hygienic measures. Vaccines are not currently available.

References

1. Gwaltney JM Jr. Virology and immunology of the common cold. Rhinology. 1985;23:265.[PubMed]
2. Myint S, Johnstone S, Sanderson G, Simpson H. An evaluation of ‘nested’ RT-PCR methods for the detection of human