How is Ebola spread?
The Ebola virus is transmitted in the bodily fluids of people who are seriously ill, who are likely to be vomiting, bleeding or have diarrhoea. Blood, faeces and vomit are the most infectious fluids, and in late stages of the disease even tiny amounts can carry high loads of virus. But a nurse who got a patient’s blood on their hands could wash it off with soap and water without any ill-effects. He or she would become ill only if they had a cut or abrasion on their hand or touched their mouth, eyes or nose, which would allow the virus to pass into their bodily fluids.
What are the symptoms?
It can take two to 21 days for symptoms to show, although usually it is five to seven days. Typically, the first signs are a fever involving a headache, joint and muscle pain, sore throat and severe muscle weakness. Many of those symptoms are similar to flu, so Ebola is not immediately obvious, though it should be suspected in anyone who has been in west Africa recently. After that come diarrhoea, vomiting, a rash and stomach pain. The kidneys and liver stop working properly. Patients may bleed internally and also from the ears, nose, eyes and mouth.
What about sweat – for example could I get Ebola from using gym equipment?
No. Nobody who had Ebola and was symptomatic, with intense muscle weakness and a fever in the early stages, would be well enough to go to the gym – and until they are symptomatic, they are not infectious. Sweat, anyway, is probably not a source of large amounts of virus – in fact, the World Health Organisation (WHO) says whole live virus has never been isolated from sweat.
How about saliva?
WHO says saliva at the most severe stage of the disease, and also tears, may carry some risk, but the studies are inconclusive. The virus has been detected in breast milk. A 2007 study in the Journal of Infectious Diseases is probably the most informative on where the virus hides.
Can I get Ebola from a toilet seat?
Yes – faeces from somebody with Ebola are a real hazard and the virus has also been detected in urine. But there would only be a danger if a seriously sick person had used the toilet and contaminated it and that is most likely in their home or hospital. Public toilets, in general, are very unlikely to be a risk.
Can it be sexually transmitted?
Yes, and the virus lasts in the semen of people who have recovered, maybe for as long as 90 days.
Could I catch Ebola from using a taxi that has taken a patient to hospital?
The virus can be transmitted on surfaces that bodily fluids have touched, so if somebody had bled or vomited on the seat, there would be a risk to anybody who had a cut or touched their face with contaminated hands. In Europe or the US, if a patient was diagnosed with Ebola, there would be a massive effort from the public health authorities to trace their movements as well as their contacts. Any taxi they had travelled in while sick would have to be decontaminated.
Could I catch Ebola from door handles a patient had touched?
Yes, if the handle was contaminated with blood, vomit or faeces, which would be more likely in the house where the patient had been living when they fell sick, or in the hospital. But if people have intact skin, do not touch their eyes, nose or mouth and frequently wash their hands, they will not get infected.
What can be done in railway stations, schools or other public places to prevent contagion?
There are strict decontamination procedures by Public Health Englandthat must be followed. Any area visibly contaminated – where there is blood, vomit or faeces – and toilets and surfaces lots of people touch, such as door handles and telephones, must be wiped with disposable towels to remove any visible fluids, then cleaned with detergent or soap and water and allowed to dry. Then they must be disinfected, for instance with diluted bleach – one part bleach to four parts water. Those who do the cleaning must be fully covered, with long sleeved shirts tucked into disposable gloves and trousers tucked into socks and closed shoes. Any cuts or abrasions must be covered with plasters. But there is no need to clean corridors or areas that the person has just passed through.
The virus is quite fragile and is easily destroyed by UV light, drying out, high temperatures (which is helpful in west Africa) and disinfectants including soapy water and alcohol gel. The longest it is likely to survive is a few days, if left in a pool of bodily fluid in a cool, damp place.
Is food safe?
Yes, if it is cooked. The Ebola virus is inactivated through cooking. Raw bush meat is a risk. Past outbreaks of Ebola in Africa came from the hunting, butchering and preparing of bush meat for people to eat.
Is Ebola virus airborne? Should I wear a mask?
No. The virus is not airborne. In spite of speculation, the UN Ebola Mission for Emergency Response says extensive studies of the virus have not shown any airborne transmission. Patients do not cough and sneeze a lot with this disease and the WHO states in an advisory notice:“Epidemiological data emerging from the outbreak are not consistent with the pattern of spread seen with airborne viruses, like those that cause measles and chickenpox, or the airborne bacterium that causes tuberculosis.”
What if somebody coughs or sneezes in my face?
There is a theoretical possibility that a person heavily infected with Ebola could cough violently and send wet, heavy droplets into the face of somebody nearby. The person most at risk of catching Ebola this way would be whoever is nursing the patient, and they would hopefully be wearing protective clothing including a mask.
Could the Ebola virus mutate to change the way it is transmitted?
Although viruses do mutate, scientists say no virus, to their knowledge, has changed its mode of transmission, and there is no evidence that it is happening with Ebola.
Are spaceman-style protective suits any good, given that some health workers wearing them have got Ebola?
They work as long as they are used properly. There are strict procedures for taking them off when the gloves and outside of the suit may be covered in virus. The US Centers for Disease Control has a guide for safe removal, to ensure bare hands do not touch contaminated material.
Are scanners the answer for detecting infected people entering the UK?
No. All that scanners can detect are raised body temperatures. That could be caused by a cold virus or even the menopause, rather than Ebola. Every person with a raised temperature would then have to have a blood test for Ebola. There are two other problems: people could arrive from west Africa by any port, not least because airlines are not flying directly here from affected countries, so logically there would have to be scanners also at the seaports and the Channel tunnel. And the biggest issue is that people are likely to arrive in the days before symptoms show, so they will not have a high temperature and there is no way to know they are carrying Ebola.