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THE SPOROZOA IN RELATION TO DISEASE IN MAN AND ANIMALS.
736 the application of leeches to the mastoid processes-and drastic purgatives should be ordered. Fluids should be given in only very small quantities. The following is one of the cases related. A man, aged 65 years, was admitted to hospital in December, 1901. Three years previously his legs began to swell and a fortnight before admission ascites appeared. There were double pleural effusion, ascites, much oedema of the legs, and slight icterus. The urine did not contain In albumin. Under treatment the oe lema diminished. to the wall abdominal and the oedenn extended April, 1902, the effusions increased. The quantity of urine diminished to one litre in 24 hours and the kidneys did not excrete methylene blue administered to test their activity. From July to October paracentesis abdominis was performed thrice. On Oct. 29th the patient was somnolent and passing urine and faeces in the bed. M. Merklen and M. Heitz were surprised to find that the oedema of the legs had almost disappeared and that the ascites and pleural effusions were no longer perceptible. The liver and spleen were enlarged. On the 30th he was semi-comatose and there were general muscular rigidity, Kernig’s sign, and dilated pupils. On the 31st there were deep jaundice and choluria and the coma was diminishing. With the improvement the anasarca and ascites returned and the quantity of urine increased to three litres in the 24 hours. He gradually regained his previous condition. On April 18th, 1933, he was readmitted. Until the 16th he had felt well and had gone about with his big abdomen and swollen legs. Then he suddenly became somnolent and simultaneously the swelling of the abdomen and limbs subsided. On admission he presented the symptoms found six months previously, but in a more severe form. On the 19th there were deep jaundice, vomiting, and melaena. On the 23rd he began to improve but the dropsy gradually returned. He died on May 31st. At the necropsy moderate ascites, chronic peritonitis, and atrophic cirrhosis of the liver The kidneys were rather small and showed were found. on microscopic examination chronic arteritis and subacute epithelial nephritis. There was slight left pleural effasion The heart was a little and the lunga were cedematous. dilated. There was marked effusion into the pia-arachnoid
spaces.
-
THE WINTER’S WEATHER AT THE CONTINENTAL RESORTS. THE following table gives a summary of the temperature and rainfall experienced at most of the principal health and pleasure resorts on the continent during the three months, December to February, of the past winter. It is permissible to speak of the winter as past in those southern latitudes, for whatever may be the case in our more northern clime spring in those favoured spots does undoubtedly commence with March. As would naturally be expected, the warmest
place or
was
about
Algiers, where the mean temperature was 56° F., equal to an average London temperature at the
beginning of June.
But
as a
drawback it will be observed
also the wettest. The resort with the lowest temperature was Florence but it was also one of the driest as regards the aggregate rainfall as well as It one of the driest in the matter ’of days with rain. should be said that a "day with rain" in the above table signifies a day when four-hundredths of an inch have fallen. After Algiers the places with the warmest were Lisbon and Naples and these mean temperature two cities had the advantage that their temperature was Li3bon’s absolute more equable than at any other spot. maximum temperature was the lowest and its total rainfall was considerably less than that at the majority of the other stations. It had, however, with Biarritz, many more days with rain than most other places. Frost was recorded by the screened thermometer at Biarritz, Florence, Nice, and Rome. At Biarritz the thermometer descended to 32° or below on no less than 11 different nights, but at Florence the number was only six and at Nice three, while Rome had but one
that it
was
mean
frost. ___
THE
SPOROZOA IN RELATION TO MAN AND ANIMALS.
DISEASE IN
Professor E. A. Minchin of the University of London delivered the first of a series of eight lectures on the sporozoa at University College, London, on Feb. 29th. During recent years the study of this important group of micro-organisms has received great attention in connexion with the etiology of such diseases as malaria, cancer, and certain tropical diseases of parasitic origin. The sporozoa, said Professor Minchin, constitute a group of protozoa widely distributed in nature and universally characterised by parasitic habits. They infest the internal organs and tissues of almost all classes of animals. There is, perhaps, no species of worm, mollusc, crustacean, insect, or vertebrate which is not liable to become the involuntary "host"of some kind of sporozoon parasite. Correlated with their wide distribution the sporozoa exhibit great diversity of anatomical characters and life-history. Yet the sporozoa as a group possess certain very characteristic features in common, peculiarities which are in direct relation with their habit of life as internal parasites. Their nutriment is always of a fluid nature-viz., the blood plasma or juices of their host, absorbed osmotically at the surface of the body of the parasite. None of the special organs for ingesting or digesting solid food, so frequent in other protozoa, are ever found in this group, while food vacuoles and contractile (excretory) vacuoles are always absent. The sporozoa are exceedingly fertile, an abundant progeny of several hundreds of motile spores (swarm spores) being formed within, and liberated from, the body of the parent. This occurs within the tissues of the host inhabited by the sporozoon. Thus the common earthworm harbours within its body a sporozoon (maonooystis agilis) which infests the vesiculi seminales and lives (endoparasitically) within the sperm mother cells. Around the margin of these cells the spermat)zoa of the earthworm develop while the parasite grows within the cell until, when it has attained full size, it is seen to be covered by a layer of spermatozoa. The growing parasite is pear-shaped and consists of a single nucleated protoplasmic body which soon issues forth from its spurious covering and leads a free life. This free parasitic stage is the sporont"stage. Sporonts when fully grown conjugate in pairs or gametes. Each pair secretes a cyst wall within which the protoplasm and nuclei undergo segmentation into numerous small oval-shaped masses of nucleated protoplasm (zygotes). Each zygote eventually divides by repeated fission into eight smaller organisms within a single shell or covering ; these are called sporozoites or falciform bodies. These zygotes undergo no further development in the body of their host the earthworm. When the latter, however, is
737 devoured by birds the sporozoites are set free and pass out tjut from the facility with which damp air and clothes allow with the fxces of the latter as individual sporozoites to be tthe natural warmth to escape. Damp clothes, in short, the within of which earthworm the swallowed a ire of heat while conductors body by again good dry clothes are insulators, Some sporozoa aand the degree at which the heat of the body is mainthe life cycle above detailed is repeated. may invade the human body and produce disease at certain ttained in bed is a measure of the insulating value of its stages of their life-history passed within the body of man, a (coverings. The risk of sleeping in damp clothes would be subject that will be fully expounded in the succeeding tthe same as if copper or tin foil were used for the purpose. lectures. The second lecture delivered by Professor Minchin ]It follows that the only practical and trustworthy test for a on March 7th discussed the life relations of two important (damp bed would be to place, say, a hot-water bottle in it classes of sporozoa-the coccidia and the gregarmas. The1and to note how rapidly the temperature of the water falls. coccidia were, he said, minute parasitic organisms whichJAccording to the principles just laid down the difference infested the intestinal canal of worms, crustaceans, and other1would be very perceptible in the case of a damp and .arthropods. They were occasionally present in echinodermsin that of a dry or well-aired bed. The so-called damp but the higher vertebrates (those above the grade ofcdetectors, which depend upon the stretching of a fibre or ] in dry air and its shrinking in moist air, give, in reality, amphibians and the tunicates) were free from these hair ] useful indication, neither does a watch glass showing the parasites. Abundant spore formation by fission was a charac-no teristic feature of these organisms, the number of sporesdeposition of moisturebeing often so great as to produce the death of the host. This phenomenon was termed death by auto-intoxication. A SANATORIUM IN THE BALANCE. The spores might enter and infect a suitable host IN dealing with the subject of tuberculosis we have from in a variety of ways-e.g , by being eaten with the food (casual infection) or by being inoculated into time to time pointed out that unless the advocates of sanathe host by a mosquito or other insect which served toriums were less optimistic in their prophecies as to the The benefit which is to be anticipated from these admirable as an intermediate host (infection by inoculation). gregarium were larger and more highly developed organ- institutions a reaction based upon èisappointment was isms than the coccidia, but their distribution as parasites inevitable. Unfortunately for the true interests of the included the same classes of animals as those infested consumptives this reaction has already set in and those by the coccidia. In a few rare cases of skin disease who have preached in and out of season that solely ‘ occurring in South America investigation has shown that by sanatoriums consumption could be stamped out"are the virus is a coccidium which is communicated from alone to blame for this regrettable result. Sanatoriums one person to another by contact. The sporozoa were have to some extent been promoted and built upon divided into two great classes—viz., the telosporidia in which the implied if not specific understanding that in allowspore formation occurred only when the animal reached the ing three months’ residence for each patient cure might be adult condition (gregarinse, coccidia, and h2emosporidia) effected and now that the necessary interval has elapsed and and the neosporidia in which spore formation took place in the prophecy has been unfulfilled the chickens of exaggerathe early stage of the life-cycle of the animal. The former tion are returning to their roost. Apparently the Heswall class contained certain sporozoa which were pathogenic to Sanatorium which was recently erected by the board of man, including the deadly malarial parasite and others guardians of the city of Liverpool on a site overlooking the which were the probable agencies in the production of ’ waters of the Dee has not passed altogether unscathed certain tropical diseases. through the criticisms levelled against its first annual report. The results, in so far as they can be gauged from the figures furnished by our Liverpool correspondent last week, do not THE PHYSICS OF THE DAMP BED. astonish us as we have never been led away by the " stampTHE question is very commonly asked as to why it is ing out"will-o’-the-wisp. Bat apparently the Liverpool dangerous to sleep in a damp bed. Some persons even deny guardians, as well as one of the medical officers of the that there is any risk, confidently recounting perhaps in institution, thought otherwise. It seems that 56 patients support of their view an experience in which no harm had were admitted during the year and of these seven died. ensued to them, even although the mattress had been acci- This fact conveys little to us unless we know the precise dentally kel-t wet through the night by the leaking of a stage of the disease on admission of the patients hot water bottle. A consideration of the physical condition and the duration of stay in each case. If the cases of the damp bed easily accounts for its danger to health were advanced or, perchance, moribund on admission the -and it does not follow that while there is risk when the figures convey no information of any value and until we coverlet is damp the risk is quite the same when the mat- receive more detailed data we shall withhold comment. At tress is superficially wet. To begin with, damp air is not only the date of the report there were 21 patients in the a conductor of heat, so that the warmth of the body when of these were reported to be improving and 18 sanatorium ; surrounded by it easily escapes, but it also communicates in three the disease was arrested. The chairman apparently a dampness to the coverlet which destroys its non-conregarded the report as disappointing but it was deterductivity. The danger of sleeping in a damp bed, however, mined in order to give the institution a fair trial to lies not so much in the dampness of the air as in the damp- keep it going for another 12 months and to endeavour ness of the clothes. The vital principle of the bed coverlet, to secure more cases in the primary stage of the disease. as it is with all clothing, is that it should be as far as possible If early cases are secured we have little doubt that non-conducting-i.e., having the property of preventing the next year’s report will be of a much more encouraging escape of the natural heat of the body. When clothing is character. But it is nevertheless much to be regretted damp it loses to a large extent this property and so the body that apparently in consequence of the admission of unloses its natural warmth, experiences a chill, and a serious suitable cases the public will receive a shock in conillness may ensue. It is therefore conceivable that no harm nexion with the institution and a shock which may, we would result if merely the mattress of a bed were wet so long fear, prevent other boards of guardians from following the as the upper coverings, the sheet, the blanket, and the coverexample of Liverpool. But whatever may be the facts with let, were perfectly dry, effectually preventing, that is, the regard to the Heswall Sanatorium it cannot be doubted that escape of the body heat. A chill does not arise from the cold professional opinion in this country is undergoing some of dampness (cold and damp are not interchangeable terms)’ change with respect to the functions of a sanatorium. With -
-
.
spaces.
-
THE WINTER’S WEATHER AT THE CONTINENTAL RESORTS. THE following table gives a summary of the temperature and rainfall experienced at most of the principal health and pleasure resorts on the continent during the three months, December to February, of the past winter. It is permissible to speak of the winter as past in those southern latitudes, for whatever may be the case in our more northern clime spring in those favoured spots does undoubtedly commence with March. As would naturally be expected, the warmest
place or
was
about
Algiers, where the mean temperature was 56° F., equal to an average London temperature at the
beginning of June.
But
as a
drawback it will be observed
also the wettest. The resort with the lowest temperature was Florence but it was also one of the driest as regards the aggregate rainfall as well as It one of the driest in the matter ’of days with rain. should be said that a "day with rain" in the above table signifies a day when four-hundredths of an inch have fallen. After Algiers the places with the warmest were Lisbon and Naples and these mean temperature two cities had the advantage that their temperature was Li3bon’s absolute more equable than at any other spot. maximum temperature was the lowest and its total rainfall was considerably less than that at the majority of the other stations. It had, however, with Biarritz, many more days with rain than most other places. Frost was recorded by the screened thermometer at Biarritz, Florence, Nice, and Rome. At Biarritz the thermometer descended to 32° or below on no less than 11 different nights, but at Florence the number was only six and at Nice three, while Rome had but one
that it
was
mean
frost. ___
THE
SPOROZOA IN RELATION TO MAN AND ANIMALS.
DISEASE IN
Professor E. A. Minchin of the University of London delivered the first of a series of eight lectures on the sporozoa at University College, London, on Feb. 29th. During recent years the study of this important group of micro-organisms has received great attention in connexion with the etiology of such diseases as malaria, cancer, and certain tropical diseases of parasitic origin. The sporozoa, said Professor Minchin, constitute a group of protozoa widely distributed in nature and universally characterised by parasitic habits. They infest the internal organs and tissues of almost all classes of animals. There is, perhaps, no species of worm, mollusc, crustacean, insect, or vertebrate which is not liable to become the involuntary "host"of some kind of sporozoon parasite. Correlated with their wide distribution the sporozoa exhibit great diversity of anatomical characters and life-history. Yet the sporozoa as a group possess certain very characteristic features in common, peculiarities which are in direct relation with their habit of life as internal parasites. Their nutriment is always of a fluid nature-viz., the blood plasma or juices of their host, absorbed osmotically at the surface of the body of the parasite. None of the special organs for ingesting or digesting solid food, so frequent in other protozoa, are ever found in this group, while food vacuoles and contractile (excretory) vacuoles are always absent. The sporozoa are exceedingly fertile, an abundant progeny of several hundreds of motile spores (swarm spores) being formed within, and liberated from, the body of the parent. This occurs within the tissues of the host inhabited by the sporozoon. Thus the common earthworm harbours within its body a sporozoon (maonooystis agilis) which infests the vesiculi seminales and lives (endoparasitically) within the sperm mother cells. Around the margin of these cells the spermat)zoa of the earthworm develop while the parasite grows within the cell until, when it has attained full size, it is seen to be covered by a layer of spermatozoa. The growing parasite is pear-shaped and consists of a single nucleated protoplasmic body which soon issues forth from its spurious covering and leads a free life. This free parasitic stage is the sporont"stage. Sporonts when fully grown conjugate in pairs or gametes. Each pair secretes a cyst wall within which the protoplasm and nuclei undergo segmentation into numerous small oval-shaped masses of nucleated protoplasm (zygotes). Each zygote eventually divides by repeated fission into eight smaller organisms within a single shell or covering ; these are called sporozoites or falciform bodies. These zygotes undergo no further development in the body of their host the earthworm. When the latter, however, is
737 devoured by birds the sporozoites are set free and pass out tjut from the facility with which damp air and clothes allow with the fxces of the latter as individual sporozoites to be tthe natural warmth to escape. Damp clothes, in short, the within of which earthworm the swallowed a ire of heat while conductors body by again good dry clothes are insulators, Some sporozoa aand the degree at which the heat of the body is mainthe life cycle above detailed is repeated. may invade the human body and produce disease at certain ttained in bed is a measure of the insulating value of its stages of their life-history passed within the body of man, a (coverings. The risk of sleeping in damp clothes would be subject that will be fully expounded in the succeeding tthe same as if copper or tin foil were used for the purpose. lectures. The second lecture delivered by Professor Minchin ]It follows that the only practical and trustworthy test for a on March 7th discussed the life relations of two important (damp bed would be to place, say, a hot-water bottle in it classes of sporozoa-the coccidia and the gregarmas. The1and to note how rapidly the temperature of the water falls. coccidia were, he said, minute parasitic organisms whichJAccording to the principles just laid down the difference infested the intestinal canal of worms, crustaceans, and other1would be very perceptible in the case of a damp and .arthropods. They were occasionally present in echinodermsin that of a dry or well-aired bed. The so-called damp but the higher vertebrates (those above the grade ofcdetectors, which depend upon the stretching of a fibre or ] in dry air and its shrinking in moist air, give, in reality, amphibians and the tunicates) were free from these hair ] useful indication, neither does a watch glass showing the parasites. Abundant spore formation by fission was a charac-no teristic feature of these organisms, the number of sporesdeposition of moisturebeing often so great as to produce the death of the host. This phenomenon was termed death by auto-intoxication. A SANATORIUM IN THE BALANCE. The spores might enter and infect a suitable host IN dealing with the subject of tuberculosis we have from in a variety of ways-e.g , by being eaten with the food (casual infection) or by being inoculated into time to time pointed out that unless the advocates of sanathe host by a mosquito or other insect which served toriums were less optimistic in their prophecies as to the The benefit which is to be anticipated from these admirable as an intermediate host (infection by inoculation). gregarium were larger and more highly developed organ- institutions a reaction based upon èisappointment was isms than the coccidia, but their distribution as parasites inevitable. Unfortunately for the true interests of the included the same classes of animals as those infested consumptives this reaction has already set in and those by the coccidia. In a few rare cases of skin disease who have preached in and out of season that solely ‘ occurring in South America investigation has shown that by sanatoriums consumption could be stamped out"are the virus is a coccidium which is communicated from alone to blame for this regrettable result. Sanatoriums one person to another by contact. The sporozoa were have to some extent been promoted and built upon divided into two great classes—viz., the telosporidia in which the implied if not specific understanding that in allowspore formation occurred only when the animal reached the ing three months’ residence for each patient cure might be adult condition (gregarinse, coccidia, and h2emosporidia) effected and now that the necessary interval has elapsed and and the neosporidia in which spore formation took place in the prophecy has been unfulfilled the chickens of exaggerathe early stage of the life-cycle of the animal. The former tion are returning to their roost. Apparently the Heswall class contained certain sporozoa which were pathogenic to Sanatorium which was recently erected by the board of man, including the deadly malarial parasite and others guardians of the city of Liverpool on a site overlooking the which were the probable agencies in the production of ’ waters of the Dee has not passed altogether unscathed certain tropical diseases. through the criticisms levelled against its first annual report. The results, in so far as they can be gauged from the figures furnished by our Liverpool correspondent last week, do not THE PHYSICS OF THE DAMP BED. astonish us as we have never been led away by the " stampTHE question is very commonly asked as to why it is ing out"will-o’-the-wisp. Bat apparently the Liverpool dangerous to sleep in a damp bed. Some persons even deny guardians, as well as one of the medical officers of the that there is any risk, confidently recounting perhaps in institution, thought otherwise. It seems that 56 patients support of their view an experience in which no harm had were admitted during the year and of these seven died. ensued to them, even although the mattress had been acci- This fact conveys little to us unless we know the precise dentally kel-t wet through the night by the leaking of a stage of the disease on admission of the patients hot water bottle. A consideration of the physical condition and the duration of stay in each case. If the cases of the damp bed easily accounts for its danger to health were advanced or, perchance, moribund on admission the -and it does not follow that while there is risk when the figures convey no information of any value and until we coverlet is damp the risk is quite the same when the mat- receive more detailed data we shall withhold comment. At tress is superficially wet. To begin with, damp air is not only the date of the report there were 21 patients in the a conductor of heat, so that the warmth of the body when of these were reported to be improving and 18 sanatorium ; surrounded by it easily escapes, but it also communicates in three the disease was arrested. The chairman apparently a dampness to the coverlet which destroys its non-conregarded the report as disappointing but it was deterductivity. The danger of sleeping in a damp bed, however, mined in order to give the institution a fair trial to lies not so much in the dampness of the air as in the damp- keep it going for another 12 months and to endeavour ness of the clothes. The vital principle of the bed coverlet, to secure more cases in the primary stage of the disease. as it is with all clothing, is that it should be as far as possible If early cases are secured we have little doubt that non-conducting-i.e., having the property of preventing the next year’s report will be of a much more encouraging escape of the natural heat of the body. When clothing is character. But it is nevertheless much to be regretted damp it loses to a large extent this property and so the body that apparently in consequence of the admission of unloses its natural warmth, experiences a chill, and a serious suitable cases the public will receive a shock in conillness may ensue. It is therefore conceivable that no harm nexion with the institution and a shock which may, we would result if merely the mattress of a bed were wet so long fear, prevent other boards of guardians from following the as the upper coverings, the sheet, the blanket, and the coverexample of Liverpool. But whatever may be the facts with let, were perfectly dry, effectually preventing, that is, the regard to the Heswall Sanatorium it cannot be doubted that escape of the body heat. A chill does not arise from the cold professional opinion in this country is undergoing some of dampness (cold and damp are not interchangeable terms)’ change with respect to the functions of a sanatorium. With -
-
.