The United States’ vital prescription drug supply chains could bend as the coronavirus outbreak highlights the global pharmaceutical system’s fragility, but they probably won’t break, experts said.

Health organizations are advising patients to secure 30- or 90-day supplies of maintenance medications. Some insurance companies are allowing early refills. But experts say Americans don’t need to worry yet – those recommendations are largely so that patients will have their medicines if they can’t go to the pharmacy and so they can maintain social distancing.

“If you’re in the US, you have a trustworthy and reliable supply of medicines. That hasn’t changed in the last two months,” said Ronald Piervincenzi, the CEO of US Pharmacopeia, an independent not-for-profit organization that develops medicine standards.

China saw a dip in drug production, but factories there are now getting back to work. India, another huge supplier, has announced it will keep some of the medications it makes on reserve. The US Food and Drug Administration has announced one drug shortage caused by the coronavirus but will not disclose what drug or where it is made.

Quick Guide What are coronavirus symptoms and should I go to a doctor? Show What is Covid-19? Covid-19 is caused by a member of the coronavirus family that has never been encountered before. Like other coronaviruses, it has come from animals. The World Health Organization (WHO) has declared it a pandemic. What are the symptoms this coronavirus causes? According to the WHO, the most common symptoms of Covid-19 are fever, tiredness and a dry cough. Some patients may also have a runny nose, sore throat, nasal congestion and aches and pains or diarrhoea. Some people report losing their sense of taste and/or smell. About 80% of people who get Covid-19 experience a mild case – about as serious as a regular cold – and recover without needing any special treatment. About one in six people, the WHO says, become seriously ill. The elderly and people with underlying medical problems like high blood pressure, heart problems or diabetes, or chronic respiratory conditions, are at a greater risk of serious illness from Covid-19. In the UK, the National health Service (NHS) has identified the specific symptoms to look for as experiencing either: a high temperature - you feel hot to touch on your chest or back

a new continuous cough - this means you’ve started coughing repeatedly As this is viral pneumonia, antibiotics are of no use. The antiviral drugs we have against flu will not work, and there is currently no vaccine. Recovery depends on the strength of the immune system. Should I go to the doctor if I have a cough? Medical advice varies around the world - with many countries imposing travel bans and lockdowns to try and prevent the spread of the virus. In many place people are being told to stay at home rather than visit a doctor of hospital in person. Check with your local authorities. In the UK, NHS advice is that anyone with symptoms should stay at home for at least 7 days. If you live with other people, they should stay at home for at least 14 days, to avoid spreading the infection outside the home.

Most pharmacies keep at least a month or two of drugs on hand, and the wholesalers who supply them have another month or two in stock, multiple experts said. Companies that produce completed medications also keep extra ingredients to ensure they can make their products. After that, the forecast is less clear.

“The vulnerability of supply for drugs that people take every day is an issue,” said Rena Conti, a health economist at Boston University. “And as China, Korea, Japan and Italy reduce exports of products, either because of facility problems in manufacturing or of staffing their facilities, or for their own national security purposes … we should expect there to be potential supply shortfalls, which might lead to shortages.

But, she emphasized: “You can have a supply shortfall that doesn’t ultimately lead to a shortage.”

While the US does have a strategic stockpile of pharmaceuticals and medical supplies, it contains things like respirators and antibiotics, not blood pressure medications or birth control pills.

One drug company, Merck, said it was not aware of any significant near-term impacts on the availability of its medicines and vaccines.

“We have also assessed potential longer-term impacts,” said spokesman Patrick Ryan. “The situation is fluid, but at this point we do not anticipate impacts to our supply chain unless disruption due to the Covid-19 outbreak is sustained over the next several months.”

Ryan added that for clinical trials, which are often the last option for critically ill people to seeking treatment, “the situation is evolving”, but the effects have been minor and manageable.

“At this point, we do not believe that any of our global studies are at risk,” he said.

Erin Fox, a drug shortage expert and senior pharmacy director at the University of Chicago, said the situation is “highlighting how fragile our direct supply chain can be”.

The US has long faced drug shortages, but mostly in hospitals, where doctors cannot always find drugs in their preferred dosage or have to use substitutes that serve the same purpose, she said. That is time-consuming and difficult.

“I think the main concern is are we going to pile on a whole bunch of new shortages on top of what we already have,” Fox said.

Drug experts say the FDA has far too little information about the percentage of drugs in use in the US that are reliant on facilities abroad.

Medicines are manufactured in three steps. First, raw biochemical ingredients are made and turned into ‘intermediaries’. Second, the intermediaries are then turned into an active form that is not readily consumable by patients. Last, those active ingredients are converted into consumable forms. Each step can happen in a different country.

US regulators know what facilities are licensed to produce medications, but they do not know how much of a given ingredient or drug they are making in a particular month.

The US has only about 14% of the sites that turn ingredients into their active forms, and India and China have nearly half, according to a study on generic drugs – which are the vast majority of what Americans take – that Conti and other researchers presented to the FDA earlier this month.

“The only way that we know where specific products are made is to go and ask the companies themselves who are making them,” Conti said. “Historically, pharmaceutical companies have viewed the location of manufacturing of their individual products as being a trade secret and the FDA has generally agreed with them.”

US lawmakers have for years been aware of the regulatory system’s knowledge gaps about drug supplies. They highlighted the problems as recently as October in a House committee hearing. Several legislators earlier this month proposed measures aimed at preventing shortages.

“The coronavirus outbreak has demonstrated how susceptible our nation’s drug supply chain is to disruptions that could have devastating impacts on our public health because of our overreliance on China for generic drugs …” said sponsor Anna Eshoo, a California congresswoman. “This legislation takes some first steps to increase what information the federal government needs to receive from drug manufacturers about ongoing shortages and requires manufacturers to have risk management plans to mitigate the impact of drug shortages that affect the American people.”