Viruses: More Friends Than Foes (Revised Edition). Karin Moelling
know about the dangerous contents. I guess what happened is that someone simply needed space in the tank and cleaned it up. Tanks are notorious for always being full and often ancient samples reappear, years after they have been put there. Sometimes this opens up new research fields, as in the case of a retrovirus with a then new oncogene Jun. Even in the refrigerator of the seminar room which I once cleaned up by myself, I discovered a pot of margarine which had survived there unnoticed for seven years in spite of daily use of the place. Probably the samples from Paris ended up safely in the steam sterilizer according to the rules — but were lost for research purposes. Even in my safety laboratories in Zurich we discovered a hole in the wall — which was not really dangerous because of low pressure in the room and sterile cabinets — but still, what an embarrassing surprise.
One late night a nurse came to my office in Zurich, her arms full of sample tubes. A pilot from the Philippines, potentially sick with SARS, was stationed in the hospital. This rang an alarm bell. First I called a colleague at the Institute of Tropical Medicine in Hamburg for advice. I had to wait, until he returned around midnight from a TV show on SARS. He then dictated a list of reagents, some of which had just that week become available in Berlin, primers for a sensitive laboratory test (a polymerase chain reaction, PCR, which I shall explain below). I thought that that would simply take too long for a high-risk patient. I suggested flying to Hamburg with the samples and analyzing them there. The transport was made possible, even without my accompanying the samples, by World Courier. About ten containers had to be packed around each other like a Russian doll. The bicycle courier for the airport was already waiting, when one container was left. I stealthily let it disappear in the pocket of my lab-coat, so as not to cause any further delay. At night the Institute from Hamburg gave the green light and informed me that the result was negative, which was also a big relief for the health-care workers at the hospital. A SARS patient arrived in Frankfurt, in Germany, and was successfully quarantined and treated — and recovered without causing a local outbreak as in Canada or Singapore. There paramilitary actions — such as daily reports of the body temperature of employees — were taken successfully. The World Health Organization was very alert and helpful in managing the dangerous outbreaks all over the world by issuing frequent reports and daily advice. Again, bats were the reservoirs of the virus, as in the case of Ebola. Bats live in colonies at high population densities and transmit viruses without becoming sick themselves — like resistant survivors — those that did become ill succumbed. Some people say that bats may have different immune systems, especially a much higher interferon level, therefore getting sick more rarely. In the meantime, therapies against SARS have been developed: inhibitors of its protease. A similar approach was also successful against HIV. Meanwhile in the United Arab Emirates, a new SARS outbreak has occurred, killing a sheik and his son and, later, others. It is most probably transmitted by camels. The virus was isolated at the Erasmus Medical Centre in Rotterdam. The location of isolation is normally used to coin the name of an isolate, so in this case it was first called EMC-virus, but is now known as Middle East respiratory syndrome, MERS-coronavirus. Infection rates are increasing. A short episode was experienced in Korea in 2015 in a hospital — and was spread through family members, because they take care of patients, while nurses as such do not exist. The virus was rapidly brought under control. Please note SARS was controlled by very old-fashioned hygiene measurements and paramilitary actions, not by a fancy vaccine or therapies.
One day my co-worker Alex came into my office: “I am so sick I am dying.” I remembered pictures of measles from virology textbooks (I am not a physician) and diagnosed measles. Alex had just come back from the Ukraine, from his grandmother’s birthday, where the Internet indicated a measles outbreak. Political uncertainties had prevented vaccination of a whole generation of people. Everybody in the Institute in Zurich was tested for measles antibodies and was vaccinated immediately if necessary; that is not too late. Alex did not go to the hospital as he was told to, but took the tram and infected a child. Fortunately, both of them recovered. Even a doctor for children recently infected the children in his practice office with measles because he had never been vaccinated. This raised a debate about mandatory vaccination of such a profession. 1.7 million people die every year of measles. Many parents decline the vaccination out of fear of side effects (autism was claimed to be such a side effect, but falsely). Measles is especially dangerous for adults, with encephalitis as a potential complication. Measles has written history, and depopulated islands; it contributed to the decline of the Mayas, influenced the outcome of the battles of Charlemagne, and accelerated the end of the Roman Empire. Measles can also affect animals. Some people may remember the extinction of numerous seals in the North Sea.
The fear of measles vaccination teaches us a lesson — vaccination is based on trust and education and correct information. The interest in vaccination plummeted when the information spread that the American Secret service ran a fake vaccination campaign by taking blood samples in a rural area of Pakistan to uncover the hiding place of Osama bin Laden. This increased refusal rates for vaccines for years.
Noroviruses are not very dangerous, but they are extremely contagious. A few virus particles are sufficient to cause an infection. The television cruise ship “Deutschland” was the first ship to be hit by noroviruses in the 1990s. It is based in Neustadt, on the Baltic, the city of my childhood. The newspapers speculated about the cause, the yellow and black quarantine flag was raised and nobody was allowed to leave or enter the ship. The head of my diagnostics department in Zurich, whom I called, immediately gave the correct answer: noroviruses. They were contaminating the drinking water that had been taken on board. This is a threat since then it could happen on any cruise ship and perhaps cause deaths among the elderly or weak passengers. Every crew now has to learn how to cope with this — isolate the infected passengers completely! A hospital close to Zurich had to be locked for several days. And a city nightline train was isolated at night in Frankfurt because of infected school kids. I should probably avoid the six-bunk couchette cabins in this train in future, though in fact I am still using them.
And what about ticks? If the doctor does not know what to say, he may have to be informed whether you were bitten by a tick. You should save the bug, if you can, for diagnostic purposes. It may have transmitted bacteria, Borrelia burgdorferi, causing Lyme disease — or a virus, the “tick-borne encephalitis” virus (TBEV). The bacteria can be treated by antibiotics, but TBEV cannot be treated at all. This can be diagnosed with the bugs. A bite is sometimes but not always noticeable by a moving red halo on the skin. At Princeton everybody knew and talked about this risk. One day, the famous John Hopfield — known for the Hopfield artificial neural network — pretended to look crazy and pointed out that the deer in his garden very often have ticks and could make him look like that. He took antibiotics just to be on the safe side after a bite. One needs to remember this if one cannot explain the cause of a serious headache. By the way: for a summer holiday in Austria, vaccination against ticks is mandatory and has to be done well in advance. Their chief virologist is a tick specialist — he must know!
New viruses are often not new, but they are easier to diagnose or show up at unexpected locations. One day the crows fell down from the sky over New York City. Within only a few years a new virus had conquered the whole of the USA, the West Nile virus (WNV). As indicated by its name, it came not from New York but probably by airplane from Israel. Mosquitoes get infected by birds and can induce encephalitis in humans. Air travel is the fastest way for viruses to spread. Within 24 hours viruses can get around the world in an airplane, often lurking in the air-conditioning system.
The public used to complain if health authorities do not take precautions or actions fast enough. We all have to learn that there are newly emerging viruses, which take us by surprise. The Zika virus is one of them I had never heard of it until early in 2016. It was for decades a local virus of monkeys in Uganda, the “Zika” forest, and then spread to over 32 countries in 2016, so that the WHO announced a “global health emergency”. The virus may cause a microcephalus in newborns in Brasilia, and brain infections and may be sexually transmitted. Again the poorest are hit the hardest. Two types of mosquitos (Aedes aegypti, which also transmits malaria and is called the yellow fever mosquito, and Aedes albopictus, the tiger mosquito) can transmit the virus, which is similar to dengue fever virus and yellow fever virus. The mosquitos need to be eliminated by insecticides or infected with bacteria so that the virus is