Tropical Diseases/Chapter 22
CHAPTER XXII
TYPHOID FEVER IN THE TROPICS, AND TYPHO-MALARIAL FEVER
TYPHOID FEVER
THE existence of typhoid fever in the tropics was for long not only ignored but actually denied, even by physicians and pathologists of repute. Formerly, the idea of malaria so dominated all views of tropical fevers that nearly every case of pyrexia, other than those of the most ephemeral description, or those associated with the exanthemata or with manifest inflammation, was relegated to this cause. When ulceration of the ileum was encountered post mortem the lesion was regarded, not as the specific lesion of the fever, but merely as a complication. More correct views prevail at the present day, and typhoid now ranks not only as a common disease in the tropics, but, to the European there, as one of the most commonly fatal. Little is known about typhoid as a disease of natives; Rogers has shown that in Calcutta, at all events, it is by no means uncommon among all classes. As a disease of Europeans it is only too familiar to the army surgeon in India and to the civil practitioner in most if not in all parts of the tropical world.
Besides being the scourge of the young European in India, typhoid is common enough in Japan, in China, in Cochin China, in the Philippines, in the Malay country, in Mauritius; the French have had large experience of it in Algeria and their West African possessions; the British have had similar experience in South Africa. It is also found in the West Indies; in Nigeria, even; in fact, wherever it has been properly looked for. Typhoid fever is, one might almost say, alarmingly prevalent among young soldiers and civilians in the East. It is very common among them during the first two or three years after their arrival. Fortunately, the liability decreases with length of residence. Apparently a sort of acclimatization, or rather habituation, to the poison is established with time, just as tends to be the case with other organic poisons. It is not unlikely that the relative exemption if—such there be—of the native races is owing to a like immunizing effect produced by, living in constant contact with typhoid and similar toxic agents, or to an attack in childhood. On visiting native cities—Chinese cities, for example—one is filled with amazement at the state of filth in which the people live, and not only live but thrive. The streets are narrow and never cleansed; the common sewer lies beneath the flagstones, and through the interstices between the stones can be seen the black, stinking slush in the sewer. The sewage is not confined in a well-laid cemented drain, but soaks through the loosely laid, uncemented stones, and thoroughly saturates the ground on which the tumble-down, overcrowded houses are built. Night soil is allowed to remain in wooden buckets inside the houses awaiting collection by the soil merchant, who sells it to the market gardener and the farmer. Urine is accumulated in earthenware jars, and is similarly disposed of. The houses are rarely swept and cleaned, hardly ever repaired. In every corner are filth and rubbish. And yet in such circumstances the population seems to thrive. Doubtless, where the European would almost surely contract typhoid and other filth diseases, the natives have obtained a high degree of immunity.
In Eastern countries little or no care is taken to prevent contamination of the wells and streams with sewage matter, and unless foreigners are very careful about boiling their drinking-water and the water in which their plates, etc., are washed, avoiding salads and all uncooked vegetable dishes, refraining from bazaar-made drinks, and protecting their food and food-dishes from flies and other mechanical transmitters of the Bacillus typhosus, they are almost sure, sooner or later, to fall victims.
It would appear that typhoid is not only a common disease among Europeans in the tropics, but that it is also a very virulent one, with a death-rate twice as heavy as the death - rate of typhoid in England. According to my experience in China, not only is the tropical form grave from the outset, but it is extremely liable to relapse. In England the death-rate is put down at about 1 in 8 attacked; but in India the elaborate and carefully prepared statistics show a death-rate of rather over 1 in 3. Typhoid in India, indeed, kills more European soldiers than does cholera.
Not only does typhoid exhibit increased virulence, but experience has shown that against it those sanitary safeguards which are found to be practically sufficient in England are by no means so effective in India. It would also appear that soldiers on the march contract the disease in passing through uninhabited country, in spite of the fact that the camp may be pitched in spots which, presumably, had never been occupied by man before, and although the men may have drunk only of water from springs and streams that were beyond suspicion of fsecal contamination. Similar testimony comes from Australia, where typhoid has occurred in the back country in lonely spots hundreds of miles from fixed human habitations. These data suggest that typhoid carriers are more numerous and varied than is generally believed, or that Eberth's bacillus, under certain conditions of soil and temperature, may exist as a pure yet virulent saprophyte, for which an occasional passage through the human body is not necessary.
Anti-typhoid inoculation.— Having observed that injection into the subcutaneous tissues of the human subject of dead cultures of Bacillus typhosus conferred on the blood of the individual experimented on the power of agglutinating and sedimenting living cultures of the bacillus, Sir A. Wright, in the hope that in this circumstance he had grounds for concluding that protection against typhoid might be conferred by some system of artificial immunization, devised such a system, and has practised it on a scale sufficiently extensive to warrant some conclusions.
During the Maidstone epidemic of typhoid in 1897, of 200 individuals, the subjects of special observation, 95 were inoculated, 105 were not inoculated. None of the former contracted typhoid, whereas 19 of the latter were attacked. Encouraged by these results, Wright proceeded to inoculate on a larger scale. In the British Medical Journalof January 20, 1900, he summarizes his results up to that date. Of 11,295 British soldiers in India, to whom his observations apply, 2,835 were inoculated, 8,460 remained uninoculated. Of the former, 27 at some subsequent time had attacks of naturally acquired typhoid; of the latter, 213 were similarly attacked; the percentages being 0.95 and 2.5 respectively. In these attacks 5 of the previously inoculated died; 23 of the uninoculated. On the assumption that the whole of the British army in India was inoculated and that the foregoing results were maintained, there would be an annual saving of over 1,000 cases of enteric and of nearly 200 lives.
Since that time Sir A. Wright, with an industry and zeal in keeping with the important stake at issue, has steadily pursued his investigations. The English garrison in Egypt and the South African War afforded opportunities to test his conclusions in other fields, and on an extensive scale. The figures appear to justify the conclusion that these inoculations lead to at least a twofold reduction in the incidence of the disease in those inoculated, and a 50- per-cent. reduction of the case-mortality. Crombie concluded from a careful and independent examination of the statistics, based on the results of inoculation as against non-inoculation in a group of 250 officers invalided from various causes from the South African War, that up to the age of 30 the advantage of a single inoculation is distinct— 27 per cent, of the inoculated being attacked, as against 51 per cent, of the non-inoculated. Beyond 30 he found the positions reversed, the advantage being with the non-inoculated. The results were better after a single than after a double inoculation, which appeared, according to Crombie's figures, to increase the liability to infection.
Since the time Crombie's statistics were compiled, anti-typhoid inoculation has been practised not only in the army in India, but also by the French in their armies in Tunis, Algeria, and Morocco, and by the Americans on the Mexican boundary, with gratifying results. These results have been amply confirmed by the extensive use of inoculation against typhoid during the Great War. Better methods of preparation and dosage have been introduced, and the reaction after vaccination has been mitigated thereby. According to Leishman, the rule is to use a vaccine not over three months old, to give two doses, the first containing 500 million bacilli, and ten days later the second of 1,000 million bacilli. The average duration of protection he considers to be two years, after which one injection of 1,000 bacilli should be given.
Details of the method of preparation and of the clinical effects of Sir A. Wright's inoculations will be found in the Lancet of September 19, 1896, and the British Medical Journal of January 20, 1900.
It is not requisite to enter further into the subject of typhoid fever, for, although this important disease is abundantly common in the tropics, it is not properly classifiable as a tropical disease; moreover, it is fully dealt with in every textbook on general medicine. It is alluded to here rather by way of warning the practitioner in the tropics against overlooking it, and against assuming that every case of fever he may encounter is malarial; and, also, of indicating the special importance to him of a knowledge of the latest views on the practical value of anti-typhoid inoculation.
TYPHO-MALARIAL FEVER
Some years ago a good deal was said, particularly in America, about " typho-malarial fever." An idea got abroad that there is a specific disease which, though resembling both, is neither typhoid nor malarial, nor any of the other recognized forms of continued fever. There is no doubt that in warm climates, besides the known fevers, there are several, if not many, undifferentiated specific fevers. But the clinical group indicated by the term "typho-malarial " is not one of these. Typho-malarial fever is an ordinary typhoid occurring in a person who has been exposed to malarial influences, i.e. who has become infected with the malaria parasite.
It has already been pointed out that the malaria germ may remain dormant for months or even years in the body, and then, on the occurrence of severe physiological strain— such as a chill, shock, excessive fatigue, and so forth— wake up again, and once more multiply and flourish in the blood and give rise to the phenomena of malarial fever. It is a recognized clinical fact, one familiar to our predecessors and much insisted on by them, that any disease process occurring in a person who has once had malarial fever is prone to take on an intermittent or periodic character; as if the previous malarial infection had left a sort of impress of periodicity on the constitution. Doubtless this is owing to the fact that in individuals with Laveran's parasite dormant in their tissues the physiological strain implied by the presence of active disease paralyses for the time being the innate protective power of the human body, and the parasite is once more permitted to multiply and work its mischief in the blood. There are few more depressing influences than typhoid. Little wonder, then, that typhoid in a malarial is often accompanied by clinical evidences of a resuscitation of the malaria germ. And so it comes to pass that an attack of typhoid in malarial countries, or in persons returned from malarial countries, is prone to assume some of the characters of intermittent or remittent fever.
Not infrequently, instead of the slowly increasing headache, malaise, creeping cold, anorexia, and day-by-day ladder-like rise of temperature, the first recognized sign of typhoid in such circumstances is a violent rigor, immediately followed by rapid rise of temperature, which, in an hour or two, mounts to 104° or 105° F., to be succeeded in a few hours by profuse sweating and a partial remission of fever exactly resembling an attack of ague. For the next two or three days these attacks are repeated, the remission becoming less complete each time. Quinine may be given; but, although the rigors and marked oscillations of temperature are checked, the practitioner is surprised and disappointed to find that the temperature keeps permanently too high, and that the typhoid state is gradually developed. Or it may be that a typhoid fever begins in the usual insidious way, runs its usual course for a week or two, and then, in the middle of what is regarded as an ordinary typhoid, rigors and temperature oscillations and other malarial manifestations show themselves. If quinine is given, these oscillations cease and the typhoid resumes its usual course. Or it may be that it is not until the end of the fever and during convalescence that these malarial symptoms are developed. Several such cases are now on record in which the malaria parasite was found in the blood.
The diagnosis between typhoid and some forms of malarial remittent is often exceedingly difficult, in certain cases almost impossible, without the assistance of the microscope and the serum test. The principal points to be kept in view are, first, the mode of incidence of the disease. In typhoid there is a gradual rise of temperature, a daily gain of a degree or so during several days, the maximum not being attained for five or six days; as against the sharp rigor and sudden rise of temperature through five or six degrees in the first few hours in malarial fever. Secondly, the characters of the gastric symptoms differ. Thus, in malarial remittent there are bilious vomiting and perhaps bilious diarrhœa, tenderness of the liver, epigastrium, and spleen, and an icteric tint of skin and sclerse; in contrast to the abdominal distension, perhaps the iliac tenderness and gurgling, and the peasoup stools of typhoid. Such signs as epistaxis, deafness, and cheek-flushing in typhoid have a certain weight, but skin eruptions in the tropics are of little aid in the diagnosis of such cases. Prickly heat, or its remains, is present in nearly everyone, sick and healthy, malarial or typhoid patient alike; so that rose spots are to be found in nearly all fevers in hot weather. None of these signs can be considered as absolutely diagnostic; all or any of them may be present in typhoid, and all or any of them may be present in malarial remittent. The only really diagnostic marks are tertian or quartan periodicity, amenability to quinine, and, above all, that supplied by the malaria parasite in the blood and the Widal serum test. In all doubtful cases the malaria parasite should be sought for; if it is found, the case has certainly a malarial element, and quinine is indicated. If it is not found, and if quinine has not been administered and several negative examinations of the blood have been made, the case is probably one of pure typhoid. Nevertheless, if the malaria parasite is found, typhoid is not necessarily excluded
No one who is proceeding to the tropics to practise medicine should fail to familiarize himself with the technique for the Widal reaction. In Europe he can fall back on the bacteriologist; in the tropics, as a rule, he cannot do this.
Prognosis and management.— Remittents under suitable treatment we expect to see recover; typhoids too often go the other way. A word of caution may be given as to prognosis and treatment. In forming diagnosis too much weight must not be attached to the presence or absence of diarrhœa; constipation is much more common in tropical typhoid than in the disease in Europe. Diagnosis, therefore, must not be too much influenced by absence of diarrhœa, and the practitioner must not be led by the presence of constipation into giving active purgatives. Purgatives are often of the greatest service in malarial remittent; but if, in consequence of a mistake in diagnosis, it is assumed that a case of typhoid is remittent, and large doses of calomel and other cathartics are administered, the result may be disastrous. If doubt exist about diagnosis, and quinine be given, it will not do a typhoid much harm. It is a good rule, therefore, when in doubt, to give quinine, but to avoid purgatives.