Table 1.
Comparison among SARS, Swine flu, MERS and COVID-19 causing viruses, persistence in the environment and prevention and treatment methods.
| Severe Acute Respiratory Syndrome (SARS) | Swine Flu | Middle Eastern Respiratory Syndrome (MERS) | COVID-19 | |
|---|---|---|---|---|
| Year of outbreak and duration | 2002– 2004 (Wang et al., 2005) | 2009– 2010 | 2012 | 2019 - present |
| Pathogen | SARS associated - Coronavirus (CoV) or SARS-CoV | Influenza A virus - pH1N1 | MERS associated - Coronavirus (CoV) or MERS-CoV | SARS associated – Coronavirus 2 (CoV-2) or SARS-CoV-2 |
| First reported | China’s Guangdong province | California, USA | Saudi Arabia | Wuhan, China |
| Infected Cases | 8439 (Wang et al., 2005; WHO, 2003a, 2003b) | 60.8 million cases in US (CDC, 2010) | 2519 (WHO, 2018) | >33 million (Dong E et al 2020) |
| Deaths | 812 (Wang et al., 2005; WHO, 2003a, 2003b) | 151,700 to 575,400 deaths worldwide (CDC, 2010) | 866 (WHO, 2018) | >1 million (Dong E et al 2020) |
| Cases in US | 73 (WHO, 2003a, 2003b) | 12,469 deaths in US (CDC, 2010) | 2 (WHO, 2018) | >7million cases; >200,000 deaths (Dong E et al 2020) |
| Case fatality rate | 11 % (WHO, 2003a, 2003b) | 0.2 % (Hayward et al., 2014) | 34.3 % (WHO, 2015) | ∼1−3% |
| Virus incubation time | 5–14 days (WHO, 2003a, 2003b) | 2 – 7 days (Jilani, Jamil, & Siddiqui, 2019) | 5 – 10 days (WHO, 2018) | 5–14 days (Jiang, Rayner, & Luo, 2020) |
| Key symptoms | Fever, dry-cough, diarrhea, dyspnea, and hypoxia (WHO, 2003a, 2003b) | A fever, cough, sinus and ear infection, diarrhea, dyspnea and hypoxia (CDC, 2010) | Fever, dry-cough, diarrhea, dyspnea, and hypoxia (WHO, 2018) | Fever, dry-cough, diarrhea, dyspnea, and hypoxia (WHO, 2019a) |
| Clinical manifestations | Acute respiratory distress requiring ventilator support; Pneumonia; Lymphopenia (WHO, 2003a, 2003b) | Acute respiratory distress; vomiting; pain or pressure in the chest or abdomen (CDC, 2010). | Adult respiratory distress syndrome (ARDS); Pneumonia; Kidney failure (WHO, 2018) | Acute respiratory distress requiring ventilator support; Pneumonia-like illness; Lymphopenia (WHO, 2019a) |
| Sample for testing | Stool, blood, nasopharyngeal or oropharyngeal aspirate and swab, Bronchoalveolar lavage (WHO, 2003a, 2003b) | Stool, blood, nasopharyngeal or oropharyngeal aspirate and swab, Bronchoalveolar lavage (CDC, 2010) | Stool, blood, nasopharyngeal or oropharyngeal aspirate and swab, Bronchoalveolar lavage (WHO, 2018) | Stool, blood, nasopharyngeal or oropharyngeal aspirate and swab, Bronchoalveolar lavage (WHO, 2019a) |
| Diagnostic methods | RT-PCR; ELISA; Virus culture and titer assay; EM; Chest X-rays (WHO, 2003a, 2003b) | RT-PCR; ELISA; Virus culture and titer assay; EM; Chest X-rays; Rapid influenza diagnostic tests (CDC, 2010) | RT-PCR; ELISA; Virus culture and titer assay; EM; Chest X-rays (WHO, 2018) | RT-PCR; ELISA; Virus culture and titer assay; EM; Chest X-rays (WHO, 2019a) |
| Treatment identified | No vaccine; No treatment exists except supportive care (WHO, 2003a, 2003b) | 2009 H1N1 flu vaccine (FDA approved); Anti-viral drugs (CDC, 2010) | No vaccine; No treatment exists except supportive care (WHO, 2018) | No vaccine, although several candidate vaccines and drugs are undergoing testing (WHO, 2019a) |
| Prevention | Social distancing; Avoid crowded areas and close contact with sick people; Wash hands often; avoid touching the face; wear appropriate personal protective equipment (PPE); Isolate immediately when experiencing symptoms or when infected (WHO, 2003a, 2003b) | Social distancing; Avoid crowded areas and close contact with sick people; Wash hands often; avoid touching the face; wear appropriate personal protective equipment (PPE); Isolate immediately when experiencing symptoms or when infected (CDC, 2010) | Social distancing; Avoid crowded areas and close contact with sick people; Wash hands often; avoid touching the face; wear appropriate personal protective equipment (PPE); Isolate immediately when experiencing symptoms or when infected (WHO, 2018) | Social distancing; Avoid crowded areas and close contact with sick people; Wash hands often; avoid touching the face; wear appropriate personal protective equipment (PPE); Isolate immediately when experiencing symptoms or when infected (WHO, 2019a) |
| Transmission route | Close contact with infected person Moisture droplets in the air when an infected person coughs, sneezes or talks Touching objects with virus contact on it and then touching the mouth or nose. (WHO, 2003a, 2003b) | Close contact with infected person Moisture droplets in the air when an infected person coughs, sneezes or talks Touching objects with virus contact on it and then touching the mouth or nose (CDC, 2010). | Zoonotic – Can be transmitted from infected animal to humans. Person to person transmission is rare, but possible. Moisture droplets in the air when an infected person coughs, sneezes or talks (WHO, 2018) | Close contact with infected person; Moisture droplets in the air when an infected person coughs, sneezes or talks; Touching objects with virus contact on it and then touching the mouth or nose (WHO, 2019a). |
| Possible airborne and fomite transmission | Yes | Yes | Yes | Yes |
| Fecal shedding reported | Yes | Yes | Yes | Yes (Chen et al., 2020) |
| Persistence of the virus on surfaces | Virus does not persist on food. At room temperature the virus can live for an average of 4–5 days and up to 9 days. Low temperatures and high humidity are favorable for the virus to thrive for longer periods. Virus is stable in: Feces for 4 days; Urine for 1–2 days; Paper, Formica surface and plastered walls for 36 h; Plastic surfaces and stainless steel for 3 days; Glass slide for 4 days (WHO, 2003a, 2003b) |
Virus is stable on stainless steel for 2 weeks; and cloth and microfiber for 1 week (Thompson & Bennett, 2017); hands for 5 min after transfer to surfaces (Bean et al., 1982); persists on glass surfaces (Amelie Dublineau, Batejat, Pinon, Burguiere, & Manuguerra, 2011). | At room temperature the virus can live for an average of 4–5 days and up to 9 days. Low temperatures and high humidity are favorable for the virus to thrive for longer periods (WHO, 2019b). MERS-CoV is stable for several hours in the air and on environmental surfaces including fomites collected from the surroundings of infected patients (Kim et al., 2016). | Aerosolized coronavirus can remain in the air for up to 3 h. SARS-CoV-2 demonstrate relatively long viability in the air for 3 h; o copper for 4 h; on cardboard for 24 h; on plastic and stainless steel for 2–3 days. Half-life in air is similar to SARS-CoV, i.e., 2.7 h; and on steel is 13 h and on polypropylene is 16 h (van Doremalen et al., 2020). |
| Persistence of Virus in water bodies | Surrogate SARS coronaviruses, transmissible gastroenteritis (TGEV) and mouse hepatitis virus (MHV) remained infectious in water and sewage for days to weeks (Casanova, Rutala, Weber, & Sobsey, 2009). In a study from China, SARS-CoV survived for 14 days in sewage at 4 degrees and for 2 days at 20 degrees. SARS-CoV persisted in Stools for 3 days; In urine for 17 days at 20 °C and in domestic sewage for 14 days (Wang et al., 2005) | Unclear | Unclear | Presence of SARS-CoV-2 in untreated wastewater was reported (Ahmed et al., 2020; WHO, 2020); however, it is still under investigation |
| Current scenario | No cases of SARS for over a decade (WHO, 2003a, 2003b) | Seasonal outbreaks persist (CDC, 2010) | MERS is an ongoing public health concern (WHO, 2018) | Ongoing global threat and concern due to spiking mortality rates (WHO, 2019a) |