There is increasing evidence emerging on the long-term health impacts of COVID-19 (long COVID). Information about the ongoing health impacts of COVID-19, including questions and answers, will be updated over time.
What is long COVID?
The term ‘long COVID’ is commonly used to describe signs and symptoms that continue or develop after acute COVID-19 (4 weeks from the initial infection). People experiencing these are sometimes referred to as ‘long-haulers’. As yet, there is no official definition of long COVID or diagnostic criteria for the condition. Organisations globally use a variety of terms for the condition including: Post-Acute Sequalae of SARS-CoV-2 infection; post-acute COVID-19 syndrome; post-COVID-19 syndrome; ongoing COVID-19; or living with COVID-19.
The presence of lingering symptoms may have a significant impact on the daily lives of those who are affected, and their family and whānau. Given the numbers of people who have been or will be infected with SARS-CoV-2 worldwide, the public health impact of long COVID could be significant.
Are there long-term health impacts of COVID-19?
Most people with COVID-19 recover completely and return to normal health. However, some people who have been infected with SARS-CoV-2 report a diverse range of symptoms beyond the time of ‘recovery’ from the acute phase of COVID-19 illness. Protracted symptoms are common following many viral and bacterial infections, including other coronaviruses.
SARS-CoV-2 is a novel virus discovered in 2019 so there is still limited information on the potential long-term health outcomes of COVID-19. However, this is a rapidly expanding area of research.
What are the signs and symptoms of long COVID?
A feature of long COVID is the wide range of reported symptoms. These can persist for weeks and sometimes months. Symptom severity can range from mild to disabling, and multiple body systems can be affected. Symptoms may be persistent, or intermittent and relapsing. Symptoms can vary from day to day. Some people may have a period of being symptom-free before relapsing. Relapses may occur in an irregular pattern or in response to specific triggers, such as physical or mental activity, stress, menstruation, heat, or alcohol.
Some of the most commonly reported symptoms include:
- Shortness of breath
- Low mood
- Difficulty concentrating, cognitive impairment or ‘brain fog’
- Chest pain (clinical assessment may be required to investigate the specific cause)
- Joint pain
- Muscle aches and pains
- Muscle weakness (this can be a reported symptom, and may also be clinically measured)
- Ongoing changes to smell or taste
- Fast-beating or a ‘pounding’ heart
- Sleep disturbances
Fatigue is the most reported enduring symptom and is also recognised as a common symptom following viral infections and some bacterial infections. More serious long-term complications have been reported but appear to be less common. These include inflammation of the heart muscle, lung function abnormalities, and acute kidney injury. People may experience new symptoms that were not present during the acute phase of their COVID-19 infection.
There is a growing list of symptoms associated with long COVID and there is a need to understand different clusters and patterns of symptoms which may point to different underlying causes.
Who develops long COVID?
We are continuing to learn about whether some people are more likely to develop long COVID. It appears to be more common among people with more severe initial symptoms but can also affect those who initially had mild or moderate COVID-19. This includes young adults with no pre-existing medical conditions. Long COVID is seen in all age groups, including children.
Some factors that may be associated with increased risk of long COVID have been identified. These include: older age; the presence of multiple underlying chronic medical conditions; a higher body mass index; being female; and experiencing more than five symptoms during the first week of illness. There is little data about the incidence of long COVID by ethnicity.
How common is long COVID?
It is not yet known how common long COVID is, for a variety of reasons:
- Studies of long COVID have used different measurement criteria and different inclusion criteria, so they cannot be reliably compared. Studies also often differ in the way they collect data.
- Studies have focused on different groups of people, different symptoms and time intervals, and used different numbers of people (different sample sizes).
- Most studies report the frequency of at least one symptom (not necessarily the same symptom), rather than a cluster of symptoms.
- Published studies may not be representative of everyone who has long COVID.
- Difficulties in accessing COVID testing in different countries may mask the true number of long COVID cases if studies require testing confirmation of the initial infection. In addition, testing policies vary between countries.
Estimates of how common long COVID is from international reports:
- The Office for National Statistics in the UK reports that 1 in 5 people who have tested positive for SARS-CoV-2 experience a range of health symptoms more than five weeks after their initial diagnosis, and 1 in 10 more than twelve weeks after initial diagnosis.
- A US National Institutes of Health review published in March 2021 states:
- At least 10% of people with COVID-19 experience at least one symptom for 12 weeks or longer.
- Of people with COVID-19 not admitted to hospital, at least 20-30% experience at least one enduring symptom around one month later and at least 10% three months later. A number also have long COVID symptoms beyond 6 months.
- Of people with COVID-19 admitted to hospital, 50-89% have at least one enduring symptom after two months.
- A study with follow up data for 110 hospitalised patients in the UK found:
- 74% reported at least one ongoing symptom 8-12 weeks after diagnosis. Breathlessness, fatigue and insomnia were the most common symptoms.
- Ongoing symptoms were reported by 59% of patients who had ‘mild’ COVID-19, 75% of patients who had ‘moderate’ COVID-19, and 89% of patients who had ‘severe’ COVID-19.
Larger studies are now underway or planned. These studies will give a better picture of how common ongoing COVID-19 symptoms are and who is more likely to have prolonged symptoms from COVID-19.
What causes ongoing symptoms?
It is likely that ‘long COVID’ is not a single condition. For example, some people may experience ongoing symptoms as a result of impacts of COVID-19 infection on the body, whilst others may be experiencing longer-term effects of COVID-19 treatment or hospitalisation. It appears that some people with long COVID are experiencing similar symptoms to myalgic encephalomyelitis / chronic fatigue syndrome.
A number of other causes have also been suggested, but as yet there is no consensus. It is also not known whether certain symptom patterns are a result of syndromes that are already recognised, or if long COVID is a unique new disease.
What are the treatment and support options for people with long COVID?
At this time there is limited information about long COVID and this can be difficult for some people who experience symptoms.
For support with management and treatment of long COVID symptoms, people should seek the help of their GP or healthcare team, particularly if new symptoms arise or symptoms worsen.
People can also free call or text 1737 anytime of the day or night to speak with a trained counsellor.
There are also online support groups for people experiencing long COVID including:
Some people find it useful to keep track of their symptoms. Keeping a log of symptoms can help identify which symptoms are of most concern and to identify patterns and changes in symptoms. This information is also useful to take to appointments with healthcare professionals. There a number of apps that can be downloaded for this purpose. An example of a paper version for tracking symptoms can be downloaded from the National Institute for Health Innovation.
Can people with long COVID receive the vaccine?
Early research suggests COVID-19 vaccines are safe for people with symptoms of long COVID. Anecdotal reports and some preliminary studies suggest that some people experience an improvement in symptoms after vaccination, indicating a potential role for vaccines as a treatment option. However, there have been few formal studies looking at the impact of vaccines on long COVID, and so far there are no peer reviewed studies, so these reports should be interpreted with caution. Further investigation is needed, and we will continue to monitor this research.
Vaccination against COVID-19 will be available to all New Zealand adults. Use the Unite against COVID-19 tool to find out when you can get a vaccine.
What is being done to better understand long COVID here globally?
Work is underway globally to carry out studies of people after their initial COVID-19 illness. These studies will be used to develop further guidance for patient care. For example, the National Institutes for Health in the US is initiating an effort to track the recovery path from COVID-19 of at least 40,000 adults and children.
Long COVID is still new and scientists and health professionals are still working out the best ways to manage and treat it. In Scotland, Ireland and the U.S. there have been announcements for large funds dedicated to long COVID patient research and rehabilitation.
What is the Ministry of Health doing to better understand long COVID?
In 2020 the Ministry of Health began to collate evidence that was emerging about long COVID and published guidance for the rehabilitation of people with or recovering from COVID-19 in June 2020.
The evidence for long COVID has evolved and the Ministry of Health is currently commissioning a longitudinal study of people who have had COVID-19 to better understand the ongoing health impact and the needs of this group of people. This work includes studying those that have had COVID-19 and recovered, and understanding the effects of those experiencing long COVID.