Coronavirus Disease 2019 (COVID-19) Outbreak
The novel coronavirus disease, labeled by the World Health Organization (WHO) as COVID-19, was first reported in Wuhan, China, on December 31, 2019. Compared to the previously identified coronaviruses such as the Severe Acute Respiratory Syndrome coronavirus (SARS-CoV) and the Middle East respiratory syndrome coronavirus (MERS-CoV), the fatality rate of COVID-19 is substantially lower but it is more transmissible, in so far as it has spread to over 227 countries, infected more than 524,096,000 people, and claimed over 6,292,000 lives to date (Worldometer, May 18). As one of the game-changers of the past decade, nanotechnology holds great promise in offering innovative solutions to a wide range of problems regarding the prevention, diagnosis, and treatment of COVID-19, in which nanotechnologists undoubtedly play a key role and shoulder their social responsibility. This webpage covers the most recent advances of nanotechnology in fighting COVID-19.
Coronaviruses are a large family of viruses that attack the upper and lower respiratory tracts in humans, causing a range of illnesses from the common cold to more serious, fatal forms. However, it is the third time in the 21st century that a coronavirus outbreak turns into a global health emergency. More than hundreds of coronaviruses have so far been identified, most of which are transmissible between animals such as pigs, camels, bats, and cats, but in some cases, a genetic mutation is all these viruses need to transmit to humans and cause never-before-seen diseases. To date, seven coronaviruses have been proved to cause human diseases, four of which are 229E, OC43, NL63, and HKU1, causing mild diseases, while the other three can be even lethal. The first is the Severe Acute Respiratory Syndrome coronavirus (SARS-CoV), which emerged in late 2002 and disappeared by 2004; the second is the Middle East respiratory syndrome coronavirus (MERS-CoV), which emerged in 2012 and still circulates among camels; and the third is SARS-CoV-2 which causes COVID-19 – first reported in China in December 2019 – and according to many scientists, is leading the world toward the grips of a pandemic.
The virions of SARS-CoV-2 are in the form of spheres with an average diameter of 125 nm, with lipid-based viral envelopes and positive-sense single-stranded RNA genomes. Virus particles of SARS-CoV-2 have four types of structural proteins: spike (S), membrane (M), envelope (E), and nucleocapsid (N) proteins, among which the S protein has a crucial role in attaching the virus to its host’s cells and enabling it to enter the cells.
The symptoms of COVID-19 are typically similar to flu, and it seems to start with a fever, followed by a dry cough and fatigue, but a runny nose, sneezing, or sore throat have only been reported in 5% of the confirmed cases. After a week or so, it can lead to shortness of breath, with around 20% of the patients needing hospital treatment. In some patients, especially the elderly and those with chronic health conditions, the early symptoms can progress to pneumonia, with chest tightness, chest pain, and shortness of breath. There have also been cases with little to no symptoms, taking up to 14 days to appear after exposure to the virus, but even an asymptomatic person may be shedding the virus and making others ill.
On the other hand, the rapidly increasing death tolls of COVID-19 have been a wake-up call for global health. Many researchers have recently turned their focus to this growing threat and a global effort is underway to halt its spread. Currently, there is no specific antiviral treatment available for COVID-19, but a wide range of pharmaceutical agents are being investigated. Meanwhile, among various fields of science and technology, nanotechnology has great potential to be of enormous help in the prevention, diagnosis, and treatment of COVID-19.
At the prevention stage, nanofiber-based facial respirators, along with nanotechnology-enabled highly effective antimicrobial and antiviral disinfectants, have been the first personal protective means that can prevent the spread of the virus; furthermore, extensive research is underway to develop a vaccine for COVID-19 based on different nanomaterials. In diagnostics, nanotechnology has shown considerable promise in designing sensors for developing quick-response COVID-19 tests. Last but not least, at the treatment phase, nanomedicines have been at the center of many researchers’ attention, some of which are currently being studied in clinical trials. Hence, nanotechnologists are carrying out their social responsibility to tackle the ongoing global health emergency. This webpage has been exclusively dedicated to the most recent achievements of nanotechnology in a battle against COVID-19.