THE COMMON COLD

Bay of Plenty Beacon, Volume 10, Issue 97, 21 February 1947, Page 3

THE COMMON COLD

TESTS ON HUMANS Facts of the concerted attack by British medical science on the common cdld were given to me by Dr. C. A. Andrewes, senior bacteriologist in the laboratories of the National Institute of Medical Research, when I visited him recently, writes lan Cox from London. It was Dr. Andrewes who, with other members of the institute’s staff, started war on influenza 15 years ago and made a vaccine which produced immunity in the laboratory. Subsequent research, carried out on the basis of that done at the National Institute, made possible the production of the vaccine now employed (most largely, perhaps, in the United States) to prevent epidemics of the disease. Dr. Andrewes stresses that this attack he is leading against the common cold is now in much the same stage as the attack on influenza was in 1933. It is practically certain that the cold is caused, just as influenza is, by a virus—an organism so small that it cannot be seen even with the aid of the most powerful optical microscope—and that it passes through all but the finest filters.

Now, one cannot study the effect of a virus or any other micro-organ-ism unless one is able to obtain specimens known to be absolutely free from other microbes. The choice of filters to '“catch” the cold virus and let other organisms go is, therefore, a matter of primary importance. Filtrates Can Be Separated In actual fact, filters made from collodion proved suitable, and it is now possible to produce a “filtrate” of the common cold virus after obtaining .specimens of it from a hu-' man being suffering from its effects. Further, as the size of the pores in these filters is known, the size of the virus can be gauged.

The next step, having isolated the virus, is to keep it alive. An organism in filtrate will not live indefinitely, and so it becomes necesary to discover if there is any material in which these minute bodies can be grown. This is what the common cold research unit is trying to do at this moment; it is experimenting in virus farming. Here the work of two Australian medical men, Drs. Beveridge and Burnet, has been of cbnsiderabie value in showing how the various parts of the chick embryo may be suitable for growing some viruses—6o different types have been tried, and more than 40 proved positive. It is not known yet, however; how far this is applicable to the virus that causes the common cold. This problem, and the endeavour to discover the best method of growing the virus and getting it to multiply, is therefore tne principal preoccupation of Dr. Andrewes and ms colleagues at the moment. Human Volunteers Respond ' The last consideration raises the question of how one is to know when' a virus is dead. They cannot be seen, except in certain conditions with the aid of a new electron microscope and even that it is not possible to ascertain whether they are active or not. The only way of discovering if they have retained their vitality, therefore, is by seeing if they are capable of infecting an animal body. As far as the common cold is concerned, the difficulty here is that the only animal, other than the human, known to be susceptible to it is the chimpanzee—which, for a variety of obvious reasons, is not a very suitable subject for large-scale experiments. The only alternative, then, has been to call for human volunteers from the general public. The response has been rapid., over 1500 having applied.

The routine at the Harvard Hospital, formerly an American army hospital in remote country near Salisbury, where the work is being carried out, is strict only so far as scientific control of experiments is concei’ned. Each volunteer is given a medical examination before acceptance to ensure that he has not already been infected with the cold virus, and has to be observe certain restrictions, designed to prevent any but intentional infection. Sterile Checks Subsequently, there is accommodation for 24 volunteers in self-con-tained fiats. They arrive usually on Wednesday, are intentionally infected (or not) with one of the virus preparations on Saturday. The object of the experiments is to determine the efficacy of several different methods of growing the virus in an active state and, in order that there shall not be any element of human error on the part of the clinical staff observing the symptoms develop, four out of every 24 volunteers are given a preparation that is sterile (that is, contains no active bodies at all) and no one except the staff in Londop knows which bottles contain this “control material.”

Sb far, Dr. Andrewes tells me, suitable material on which the virus may be grown artificially has not been discovered, but valuable results have already been obtained in connection with the problem of storing and preparing filtares. This, though, is only a very early stage, in an investigation that may take two years or longer to complete.