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Author: Yan Ling Apollonia Tay, Medical Student, University of Otago, Wellington, New Zealand. DermNet NZ Editor in Chief: Adjunct A/Prof Amanda Oakley, Dermatologist, Hamilton, New Zealand. Copy edited by Gus Mitchell. March 2020. Reviewed by Dr Louise Reiche, Dermatologist, Palmerston North, New Zealand. Updated June 2020 by Medical Editor: Dr Helen Gordon, Auckland, New Zealand.
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Please note that DermNet’s page is a summary about COVID-19 and may quickly become outdated.
Refer to Government websites for up-to-date information about COVID-19.
*Credit: CDC COVID-19 website
^Credit: New Zealand Government Unite against COVID-19 website (March 2020)
COVID-19 (coronavirus disease 2019) is an illness caused by the coronavirus designated 'SARS-CoV-2' that may lead to serious respiratory disease and can be fatal . The first human cases were reported in China in December 2019, and the infection rapidly spread throughout the world. The World Health Organisation (WHO) declared on 11 March 2020 that the COVID-19 outbreak was officially a pandemic.
In response to the pandemic, vaccines for COVID-19 have been developed as of November 2020. Some vaccines, such as the Pfizer/BioNTech vaccine, were given emergency approval in the US, EU, and UK in late 2020, with vaccination programs commencing soon after. As of December 2020, New Zealand has made vaccine purchase agreements with Pfizer/BioNTech, Janssen Pharmaceutica, Novavax, and AstraZeneca, with country-wide vaccinations expected in mid-2021.
[see COVID-19 immunisation and immunomodulators/biologic agents]
On June 8th, New Zealand was declared free of COVID-19 but continued to maintain closed borders with cases contained at border quarantines. Despite this, COVID-19 re-appeared in New Zealand in August 2020.
New variants of the virus are emerging, some of which appear to be more easily transmissible.
See also Dermatology patients and COVID-19.
COVID-19 affects people of all ages. Older persons and those with underlying chronic medical conditions have a higher risk of developing severe, life-threatening illness [1]. However, young and otherwise healthy people can also become very sick and may die.
The most common underlying chronic medical conditions that are reported to result in more severe disease include [2]:
Those who are immunocompromised are thought to also be at risk, but this has not yet been demonstrated in clinical studies.
The SARS-CoV-2 virus is found in droplets spread by an infected individual coughing, sneezing, talking, or touching items. The droplets may land on surfaces such as door handles, computer keyboards, and tabletops. The virus remains infectious for several days on smooth surfaces but for shorter periods on paper, wood, or cloth [3].
An uninfected individual may touch an invisible droplet then touch their face, transmitting the virus through the mucous membranes of their mouth, nose, and eyes, resulting in infection.
The incubation period for COVID-19 is generally less than 14 days; for most, the onset is 4–5 days after exposure [2].
Patients are infectious for a couple of days before becoming unwell, when unwell, and for some time after clinical recovery from COVID-19.
Infected people without symptoms are also infectious. Although their rate of spreading the infection is about half of those with symptoms, worldwide this group is thought to contribute to the spread of the SARS-CoV-2 virus tenfold.
In countries with rapid community spread, restrictions on movement and crowds are required to prevent a logarithmic increase in cases.
The severity of COVID-19 is variable. Some people infected with the virus SARS-CoV-2 do not develop any symptoms. Approximately 80% of patients have mild symptoms or are asymptomatic and approximately 20% have shortness of breath that develops around 5–8 days after onset [2]. Those with shortness of breath can rapidly deteriorate, and therefore should be admitted to hospital for assessment and management.
The most common symptoms of COVID-19 are:
Less common symptoms include:
Skin rashes have been frequently described in patients with COVID-19 with approximately 20% reporting skin rashes to be the only clinical sign of COVID-19 [16]. The most common cutaneous manifestations include [2,5]:
Other cutaneous manifestations have also been reported in association with COVID-19.
[for more images see https://covidskinsigns.com]
The complications of COVID-19 include hypoxia due to viral pneumonia, and in those requiring intensive care, hypoxic respiratory failure most often due to ARDS (Acute Respiratory Distress Syndrome). Other complications include [2]:
COVID-19 is diagnosed using nasopharyngeal (respiratory) swabs. These real-time reverse-transcriptase polymerase chain reaction (rRT-PCR) tests detect the SARS-CoV-2 virus. Tests for other respiratory infections such as influenza and respiratory syncytial virus (RSV) may be done at the same time. Saliva tests have also been developed for rapid screening and where nasopharyngeal swabs are not regarded as appropriate.
Antibody blood tests indicate whether someone has previously been exposed to SARS-CoV-2 and have mounted an immune response. They can be used to determine if weak positive PCR swabs are due to old infection.
The diagnosis of COVID-19 may also be made clinically where the patient has been in contact with a COVID-19 patient, where community infection is widespread, or the patient has recently travelled from a country with community infection.
Blood tests that have been associated with increased disease severity include [2]:
Breathless patients should have their oxygen saturations checked and monitored. Levels of oxygen saturation < 94% on air is considered a marker of severity [2].
As SARS-CoV-2 is excreted in the faeces of infected people, testing of sewage plants has become routine in some countries with low rates of infection. It can warn health authorities the virus is in the local community and nasopharyngeal testing should be increased.
The treatment of COVID-19 varies depending on severity. Those with mild disease are best to remain at home to reduce the risk of transmission in the healthcare setting.
Hospital care is required typically due to shortness of breath from viral pneumonia or in severe cases ARDS. Treatment for ARDS may include delivery of low-flow oxygen. If a patient has a higher oxygen requirement this may be delivered via high-flow nasal cannula (HFNC), non-invasive ventilation (NIV), or intubation with mechanical ventilation.
Venous thromboembolism prophylaxis (VTE) should be given to all hospitalised patients unless contraindicated. Patients requiring oxygen or mechanical ventilation should be offered low dose dexamethasone, with reported improved outcomes [6].
Other treatments include remdesivir (an anti-viral medication), and convalescent plasma (a blood product containing antibodies from those who have recovered from the disease) [2].
COVID-19 can be prevented — this is why many countries have enforced a ‘lockdown’ and have required people stay at home.
The following personal health practices are strongly encouraged to reduce the risk of infection.
Keeping a minimum distance between yourself and others to prevent physical contact and possible contamination is an essential step in preventing the spread of the virus.
Handwashing is the most effective way to prevent infection.
Practice these hygiene measures to prevent the spread of the virus through droplets or physical contact.
Many countries require incoming travellers to enter supervised quarantine for 14 days, together with nasopharyngeal swabs on arrival and before release into the community. Close contacts of infected people are asked to self-quarantine and undergo testing.
The outcome for COVID-19 depends on the severity of the illness. Up to 20% of cases require hospital admission. Approximately 5–8% of all cases require care in an intensive care unit (ICU) [2]. The reported mortality rate for ICU admissions varies greatly but is around 50% [2].
Mortality from COVID-19 is greatest in older people, especially those over 70 years. Mortality is higher in those with comorbidities associated with severe disease. For example, one-in-four cardiac transplantation patients infected with COVID-19 died from the infection [12]. The overall mortality is thought to be around 2–3% [2].
Typically, those with mild symptoms will recover within 2 weeks, however, severe cases can take three to six weeks or sometimes longer [1,2]. Some are describing variable and often debilitating symptoms for months after contracting the infection and this is under active investigation.
For current statistics, see the WHO Coronavirus Disease (COVID-19) Dashboard and the WHO's situation reports.
As of 18 April 2021, COVID-19 infection was officially reported for 140,322,903 patients with 3,003,794 deaths. On 18 April, there were 2,595 confirmed and probable cases in New Zealand with 26 deaths.
As of 14 April 2021, a total of 751,452,536 vaccinations have been administered.
In New Zealand, refer to:
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