WEBVTT 00:00.000 --> 00:10.325 [...] 00:10.325 --> 00:12.714 [The Filariasis Research and Control Unit, Georgetown, British Guiana presents] 00:12.714 --> 00:16.761 [Filariasis in British Guiana] 00:16.761 --> 00:27.868 [Produced by The British Guiana - United States of America Technical Assistance Development Organization Ministry of Labor, Health and Housing] 00:27.868 --> 00:34.834 [and the U.S. Agency for International Development] 00:34.834 --> 00:40.071 This is Georgetown, capital of British Guiana on the northern coast of South America. 00:40.071 --> 00:47.697 It is populated by the descendants of Africans, East Indians, Portuguese, Chinese, Europeans, and South American Indians. 00:47.697 --> 00:55.518 The commercial center of Georgetown lies close to the waterfront. Here are modern buildings, department stores, and supermarkets. 00:55.518 --> 01:03.287 There are also churches and cinemas. 01:04.946 --> 01:15.822 The coastal railroad parallels the coastal highway running eastward from Georgetown. Another paved highway runs 25 miles south to Atkinson airfield. 01:17.523 --> 01:42.000 British Guiana has an agricultural economy, chiefly sugar and rice. The industrious Guianese tend their farms well. This is a native rice plantation. 01:51.353 --> 02:02.949 Fishing is popular and productive and helps to vary the diet. 02:02.949 --> 02:11.030 In American Indian villages, women make bread and many dishes from cassava, their staple food. 02:16.546 --> 02:23.116 Local high schools prepare students for university entrance and a national university is being established. 02:23.116 --> 02:29.726 The people of British Guiana are great sports enthusiasts. If these people were deprived of the use of their limbs, 02:29.726 --> 02:35.206 they would not only be denied much pleasure, but they could no longer tend their farms or make a living. 02:35.206 --> 02:43.906 That is why it is so important that they understand British Guiana's crippling disease, filaria. 02:43.906 --> 02:51.180 Filaria, or filariasis, is carried by mosquitoes and may lead to swelling of the legs, arms, and other parts of the body after years of repeated infection. 02:54.260 --> 02:59.350 The disease is more often seen in females because their legs are exposed. 02:59.350 --> 03:05.385 Before a swelling appears, the blood of the infected person contains young embryo worms called micro filari. 03:05.385 --> 03:10.874 These micro filari can be seen in the infected person's blood only at night. 03:10.874 --> 03:20.055 When a female filaria mosquito feeds on the infected person's blood, it sucks up these micro filari which then pass into the stomach of the mosquito. 03:20.055 --> 03:27.427 In the mosquito's stomach, the micro filaria remains active for a short while, then bores through the wall of the stomach and moves to the thorax, or chest region of the mosquito. 03:29.734 --> 03:34.280 In a muscle fiber of the thorax, the young larva grows short and thick, until it becomes shaped like a sausage. 03:39.713 --> 03:46.793 Then it enters into the second stage and gradually grows longer and narrower until it becomes an infective larva. 03:46.874 --> 03:56.201 It wriggles its way from the thorax to the head of the mosquito and enters the proboscis, or beak. 04:05.863 --> 04:14.483 When the infected mosquito bends down to bite again, the infective larva crawls out of the proboscis and drops onto the skin of the person being bitten. 04:14.483 --> 04:27.630 Then it goes into the skin and travels around the person's body. In about a year, it becomes a sexually mature male or female worm. 04:32.983 --> 04:49.683 The worms mate and the eggs develop into micro filari, which appear in the person's blood, thus completing the cycle. 04:49.817 --> 04:56.323 One of the main methods of detecting whether one has filaria before the swelling appears is by making a blood smear. 04:56.457 --> 05:08.187 Blood is taken from a finger at night. Early in the morning the micro filari go deep into the body. If there is at least one micro filaria present, the person is said to have positive blood. 05:08.187 --> 05:18.848 If his blood is negative it does not necessarily mean that he is free of infection. This is because the worms may have entered the person's body recently and are not mature enough to produce the micro filari. 05:19.357 --> 05:25.237 Also when a person already has a swelling, his blood is usually negative. 05:25.237 --> 05:37.809 There are many effects of filaria. Long-standing infection may lead to swelling of the limbs called elephantiasis. At first, tissue fluid or lymph accumulates, but later there are permanent changes in the tissues themselves. 05:39.924 --> 05:48.034 The disease cripples physically, mentally, economically, and socially. The most damaging effect is felt by the wage earner and his family. 05:48.168 --> 05:54.723 A job is not readily given to a person who has elephantiasis if he has to stay on his feet all day long. 05:55.017 --> 06:02.187 Young girls having elephantiasis usually are denied romance and marriage because of their permanently swollen limbs. 06:02.187 --> 06:12.390 The depressing state which this disease leads to is one of its most damaging effects. If he does have a job, he has to carry out his duties the best he can even with his legs swollen. 06:17.770 --> 06:26.730 Convinced that something could be done about the filaria problem, the governments of British Guiana and the United States of America have been working together to solve it. 06:26.730 --> 06:36.623 On April the 29, 1961, representatives of the Ministry of Health and the United States Agency for International Development agreed to finance a joint filariasis research and control project. 06:38.497 --> 06:45.407 This project comes under the Technical Assistance Development Organization, abbreviated as TADO. 06:45.407 --> 06:49.904 The United States Government has supplied money, equipment and three experts: 06:49.904 --> 06:56.267 A medical entomologist who studies the mosquitoes in order to determine which ones transmit filariasis from person to person, 06:56.890 --> 07:10.900 a parasitologist who studies the parasites or worms which cause the disease, and a health educator who informs the public concerning the disease and secures their cooperation while control measures are being undertaken. 07:11.114 --> 07:21.135 The Ministry of Health has long worked to control filariasis. In 1955, an energetic Guianese doctor began a countrywide campaign to control the disease. 07:21.777 --> 07:27.277 This campaign was carried out for about six years prior to the present joint program. 07:27.277 --> 07:34.317 In the filariasis clincs, Guianese doctors studied increase or decrease in size of limbs by displacement of water. 07:34.317 --> 07:40.187 The patient steps into a water-filled drum; water comes out of the spout and is measured. 07:40.187 --> 07:49.570 Blood tests are also taken at night in the filariasis clinics so that the patient's case history will be complete. 07:54.682 --> 08:06.742 Clinics are held, not only in Georgetown, but also in the coastal villages having much filariasis. 08:13.032 --> 08:18.730 In the headquarters building of the filariasis research and control unit, there are offices and laboratories for entomology, parasitology, clinical, and health education sections. 08:24.136 --> 08:34.316 The United States medical entomologist has trained Guianese personnel in many apects of entomological work with filaria mosquitoes, both in the field and the laboratory. 08:34.316 --> 08:37.110 The United States parasitologist has trained Guianese in taking blood smears and identification of filaria parasites found in the smears. 08:42.409 --> 08:53.769 A typical filarial area along the east coast, including Buxton and surroundings, was selected as the first area for working techniques of controlling filarial mosquitoes and the filarial worms. 08:53.769 --> 09:01.490 The health education section of the filariasis unit has prepared pamphlets and posters for educating the public concerning the nature and cause of filariasis and how the public can cooperate to help control the disease. 09:06.843 --> 09:15.753 Lectures, conferences, and discussions are held just before the night blood survey teams visit a filarial area. 09:15.753 --> 09:23.315 After the health educators have paved the way, the night blood-survey teams go from house to house in the filarial villages and take a blood smear on each member of every family. 09:25.510 --> 09:34.950 This provides important basic information as to the number of persons having young filarial worms in their blood. 09:34.950 --> 09:36.330 In the interior of British Guiana, the native Indians have two other types of filariasis which do not result in swellings. 09:41.656 --> 09:49.646 Blood surveys among these Indians can be held in the day because the micro filari are present in the blood at all times. 09:49.646 --> 10:05.061 The blood smears are taken to the parisitology laboratory where they are stained so that the worm-like micro filari can be easily seen. 10:13.198 --> 10:24.991 Each morning, entomology field teams spend the first two working hours in collecting adult and aquatic stages of mosquitoes. 10:32.378 --> 10:45.780 All kinds of mosquitoes are collected in order to determine how many different kinds are carrying the filarial worms. 10:51.106 --> 10:59.106 Inside houses, filarial mosquitoes are found mostly on walls and on hanging objects such as clothing, curtains, and mosquito nets. 10:59.106 --> 11:03.289 They are also found on or under furniture and in empty containers or receptacles. 11:05.296 --> 11:19.864 The mosquitoes are sucked into a collecting tube and transferred to cages. 11:24.976 --> 11:25.980 Another type of filarial mosquito is usually found in bushy areas. 11:31.333 --> 11:39.003 In the coastal trains, mosquitoes can easily be transported for many miles. 11:39.003 --> 11:45.105 In British Guiana, drums containing water are a second source of breeding of the main filaria mosquito which is called Culex. 11:47.380 --> 12:02.660 The filaria mosquito also breeds in large tanks, some of which are inaccessible for control work. 12:02.660 --> 12:15.170 In this country, the main filaria mosquito breeds in drains only when they have become contaminated with waste. 12:20.603 --> 12:35.193 The female Culex mosquito lays its eggs on the surface of the water. They are cemented together to form a small raft about one-eighth of an inch long. 12:35.193 --> 12:46.050 A single dip into a latrine will often yield hundreds of wormlike larvae and comma-shaped pupae of Culex. The adult mosquito emerges from the pupa, dries itself, and flies away. 12:46.746 --> 12:53.516 It usually takes only seven to ten days for the complete development from the egg to the adult. 12:53.516 --> 12:57.900 The water stages of the second kind of filarial mosquito, which is called mansonia, are found associated with certain water plants, especially the water lettuce. 13:03.333 --> 13:16.123 The mansonia larvae and pupae cannot breath the air at the surface of the water like Culex. Instead, they attach themselves to roots and leaves of water plants which have air cavities and suck up the oxygen which they need. 13:16.123 --> 13:20.336 The larvae feed while hanging from their place of attachment. 13:22.236 --> 13:35.306 The Culex mosquito can be controlled in two ways. First, pit latrines are sprayed with gas oil. Only one such spraying is needed each month to prevent breeding of the Culex mosquito. 13:35.306 --> 13:42.388 Each time the latrine is sprayed it is marked with paint. This provides a record of the number of times the latrine has been sprayed. 13:43.690 --> 13:52.200 The easiest way to control filaria mosquito breeding in drums is to empty them and keep them turned upside down when water is not being stored. 13:52.414 --> 13:57.410 If it is necessary to store up water, a tight-fitting drum cover should be made of wood or metal. 13:58.024 --> 14:02.700 It should be tightly replaced after each time that water is drawn from the drum. 14:02.700 --> 14:05.368 The cover should be solid if the drum is not kept under a drain pipe. 14:05.890 --> 14:16.602 If it is kept under a pipe, the hole in the center of the cover should be covered with a fine screen in order to prevent the mosquito from laying its eggs on the water. 14:22.169 --> 14:26.202 There should be no gap or hole whatsoever in the fitted cover. 14:27.246 --> 14:34.846 Sleeping under a mosquito net will prevent the mosquito from sucking infected blood or depositing filarial worms on the skin. 14:34.846 --> 14:41.007 The most important means of controlling filariases is by giving out a drug called Vanicide or Hetrazan. 14:41.569 --> 14:54.329 When taken as directed, this drug kills the micro filari in the blood. In British Guiana, a single course of treatment is taken over a period of seven days in gradually increasing dosages. 14:54.329 --> 15:06.166 After the first day while the drug is acting on the micro filari, the person may not feel well. In spite of this you should continue with the full treatment, because the illness indicates that the drug is killing the worms in the blood. 15:07.906 --> 15:20.096 After the very active micro filari are killed, the blood becomes free of filaria worms. The filaria mosquitoes cannot then pick up the worms while feeding on this person. 15:20.096 --> 15:27.480 The control of filaria cannot be done in a short time. It involves much cooperation between the public and health personnel. 15:27.480 --> 15:33.334 If each person who is given the drug takes it in full without fail, then elephantiasis will become a thing of the past. 15:34.485 --> 15:39.725 The worms in the blood will be killed and the mosquito will not be able to pass them on to another person. 15:39.986 --> 15:46.036 When the night blood collecting teams come to your house, cooperate with them and let them take blood from your finger. 15:46.036 --> 15:51.908 Don't let yourself become deprived of the use of your legs. You can avoid becoming crippled by filaria. 15:52.283 --> 15:59.607 Take the advice of the health authorities who have been doing their utmost to help eliminate this crippling scourge. 16:02.979 --> 16:10.166 [Technical Advice and Photomicrography: George Burton, Ph.D., Public Health Service. Photography: M. Ali, audiovisual, Spec. Ministry of Health. British Guiana] 16:14.560 --> 16:19.302 [The End M-673]