The Centers for Disease Control and Prevention confirmed a 14th case of novel corona virus in the country Wednesday.
The patient in California is said to be among those evacuated from China last week and under federal quarantine at a U.S. military base.
The novel coronavirus that has spread globally since first being identified in pneumonia patients in the Chinese City of Wuhan at the beginning of the year continues to challenge health care experts.
Its rate of infection appears to be slowing in China, but it remains unknown whether this is a temporary pause.
China is currently reporting a total of 44,653 cases of the respiratory virus and 1,113 deaths. Some 24 other countries are reporting at least 395 cases, according to the World Health Organization.
During a news conference Wednesday, Dr. Nancy Messonnier, director of the National Center for Immunization and Respiratory Diseases, warned of the potential for “community spread” even in the U.S. where containment measures have been in place to minimize public exposure.
These include enhanced health screening measures at 11 U.S. airports; barring foreign nationals who have visited China during the last 14 days from entry, and a 14-day quarantine at one of four U.S. military bases of American citizens evacuated from China.
Messonnier said the country “can and should be prepared for this new virus to take a foothold in the U.S.”
She also said some of the 200 kits sent last week to designated state public health laboratories as well as more than two dozen countries to help speed up testing for the virus in conjunction with the CDC malfunctioned in trial runs, giving inconclusive results, and that the CDC is investigating why this happened with some of the kits.
The U.S. Food and Drug Administration had given emergency use authorization, that is accelerated approval, for the diagnostic test developed by the CDC to be used to evaluate suspect samples for what the WHO has named COVID-19, that is, coronavirus disease 2019.
There are a total of 427 people under investigation to date for the virus in the U.S., with 347 testing negative, 66 pending and the 14 confirmed.
There is much clinically that remains unknown about COVID-19, including the severity of the disease, its transmission and whether it will sustain itself in the population. Experts continue to debate whether the virus will be eventually contained and die out or become established and result in seasonal outbreaks.
WHO health officials said this week that the new respiratory disease virus appears to result in mild symptoms in about 80 percent of cases; pneumonia in about 15 percent and 3 to 5 percent of cases require intensive care.
The number of cases and deaths reported from the virus in China has been attributed in part to a failure on the part of government officials to acknowledge and contain it early and a health system quickly overwhelmed in terms of the ability to treat and isolate infected patients.
There have been only two reports of deaths outside of Chine from COVID-19.
Theories being investigated are that the virus, similar to other coronaviruses, originated in bats and spilled over into humans through an intermediary host animal. The virus was first linked to a seafood market in Wuhan, although at least one study of the first clinical cases raises the possibility that the virus was in circulation in that city prior to its link to cases at the market in December.
Coronaviruses are RNA viruses and the respiratory infections they can cause in humans can range from mild to severe. Some of these viruses invade the upper respiratory tract – the nose and the throat – while others invade the lower respiratory tract and can lead to pneumonia.
Common prevention measures include frequent hand washing, remaining home when sick and avoiding close contact with anyone coughing or sneezing and similarly covering one’s mouth or nose when doing the same.
There are no drugs or vaccines approved for the new virus, though research efforts are ongoing, but at least one Chinese hospital has started a clinical trial with an antiviral medication whose brand name is Kaletra and that has been most used in the United States to treat HIV patients. It belongs to a class of drugs known as protease inhibitors because they block a key enzyme that helps viruses replicate.
Its combination of two drugs – lopinavir and ritonavir – is said to have shown some clinical benefit with patients infected by SARS, or Severe Acute Respiratory Syndrome in 2002, caused by a coronavirus that is said to have some clinical similarities with COVID-19.
There is also discussion around the use of remdesivir, which was developed as a vaccine for Ebola, to be used an antiviral with COVID-19 as it has been shown to lessen lung disease in mice with Middle East respiratory syndrome (MERS), also caused by a coronavirus.
Dr. Armando Paez, an infectious disease doctor at Baystate Medical Center, was asked about the use of antivirals medications to treat COVID-19.
Are you surprised that an HIV drug – Kaletra – is being used to treat coronavirus patients in China?
No. Lopinavir/ritonavir is a protease inhibitor. Coronavirus uses protease enzyme in viral replication. This can be a potential target to block viral life cycle. Kaletra has been investigated and used to treat other coronaviruses such as SARS-CoV.
What mechanism do antiviral medications now in use against RNA viruses have to address within the body to stop the complications from the infection?
Antiviral medications can block viral replication but the body’s immune response to the infection is important as well in the manifestations and complications of the infection.
The National Institutes of Allergy and Infectious Diseases is said to be testing – or planning to test – Kaletra as well as interferon-beta and remdesivir for activity against COVID-19.
Remdesivir which was developed for Ebola seemed to be effective in treating the first patient confirmed with an imported case in the U.S., according to a report in the New England Journal of Medicine.
How hopeful are you based on what is currently known about COVID-19 that one of these or another existing antiviral might prove effective?
I am hopeful that any of the above antiviral agents being investigated can, at least, decrease complications and mortality associated with coronavirus infection.