Taming of the mozzie
QUESTION According to an article in the Daily Mail, there was malaria in Italy during the last war. How was it eradicated? AT THE turn of the 20th century, malaria was present throughout the Mediterranean basin and in Eastern regions, including European Russia. In the 19th century, it had even been as far north as England and Holland, but following improvements to healthcare, it had been eradicated.
Malaria is a potentially fatal blood disease caused by a parasite that is transmitted to human and animal hosts by the female Anopheles mosquito when it bites its victim.
By the early 20th century, the disease had reached epidemic proportions in Italy, claiming between 15,000 to 20,000 lives a year. About a third of the country, in particular marshy or low-lying areas, was affected, and malaria was severe along the Tyrrhenian and Ionian coasts, especially around the Pontine marshes, in the low Veneto, Tuscany (Maremma), Southern provinces and the islands of Sardinia and Sicily.
In 1900 and working on the recommendations of physician and social reformer Angelo Celli and the Italian School of Malariology, the Italian Parliament adopted new laws to tackle the disease. The production and free distribution of quinine was regulated by law, and spraying measures, using petroleum derivatives and aimed at reducing the larval breeding places of Anopheline mosquitos, were introduced.
Mortality rates fell almost immediately, but the outbreak of World War I disrupted the process, and by 1918 numbers dying were back to 19th-century levels.
Spraying was stepped up after the war, and in 1921 the more powerful chemical agent Paris Green (copper acetoarsenite) was introduced.
In 1930, the American Rockefeller Foundation provided a grant for the foundation of the National Laboratory of Public Health and School of Public Health in Rome.
Inaugurated by Mussolini in 1934, and under the direction of Prof Alberto Missiroli, the primary task of the malariology laboratory was to test new chemical products for malaria prevention and control.
Until the outbreak of World War II progress was made, but in October 1943 the Germans began to flood areas which had been reclaimed, and damaged drained areas of the Pontine marshes to hold back the advance of Allied forces. This caused another peak in malaria cases
The end of the war coincided with the introduction of the insecticide DDT (dichlorodiphenyltrichloroethane), since banned. The Italian government began a programme of spraying the interior walls of all houses and outbuildings, and the results were spectacular — malaria was virtually eradicated by 1949. The indoor treatment of houses, stables other rural structures continued into the mid-Fifties, and the World Health Organisation declared Italy malaria- free on November 17, 1970. Similar DDT initiatives have been successful throughout the Mediterranean, Asia and the Americas, and today, more than 90 per cent of all malaria cases are found in Africa.
There the lack of progress in tackling the disease is down to many factors: poor leadership, poor management and funding of malaria control programmes, poverty, civil unrest, corruption and, above all, resistance to anti-malarials and insecticides, largely fuelled by often unrestricted agricultural use.
Adrian Singh, Cambridge.
QUESTION Why was the rescue signal changed from SOS to Mayday? SOS was first recognised as a distress signal by the German government on April 1, 1905, and was adopted by International Radiotelegraphic Conventionon November 3, 1906.
The simple combination of three Morse dots and dashes made it suitable for use by amateur sailors as well as professional radio operators, although advances in telecoms, especially by satellite, have meant that the use of Morse code as a messaging system has all but ceased except among enthusiasts.
With the introduction of the Global Maritime Distress Safety System (GMDSS) in 1999, it became illegal for merchant shipping to use SOS for distress calls via radio, although it can still be used as a visual signal and by leisure craft.
Mayday was never used as a Morse distress signal, and rarely by ships until World War II. It was introduced only for use in voice radio signals from aircraft.
It derives from the French venez m’aider (come and help me) and was created in 1923 when an operator called Frederick Mockford, working at Croydon aerodrome, was asked to suggest an emergency code word easily understood by pilots and radio operators worldwide.
Maritime voice signals, like those on aircraft, were originally transmitted on the VHF band (100 to 200 Mhz), but because VHF signals are ‘line of sight’ they are usable only when the transmitter and receiver are ‘visible above the horizon, so a ship has to be within sight of land or another ship.
For this reason, Morse code was transmitted on frequencies that had ‘over the horizon’ capabilities, such as long wave and short wave (below 500 Khz and 3 to 30 Mhz respectively). GMDSS overcomes the disadvantages of VHF by using multiple communications and location systems, including VHF, GPS and satellite communications. The Mayday code word is repeated three times to overcome background noise and signal deficiencies and to distinguish it from a message that might just be referring to the first day of May.
It is still the accepted international voice distress signal and is always followed by who is making the call, his or her location and what has happened nature. The signals take precedence over other radio messages. Bob Cubitt, Northampton.
QUESTION It’s wellknown that the U-boats of both World Wars sank many thousands of tons of shipping by using torpedoes. So what was their deck gun for? FURTHER to earlier answers, author Kenneth Poolman (Escort Carrier, 1983) relates events when a Swordfish torpedo bomber, nicknamed ‘Stringbag’, from the carrier Vindex on North Russian convoy duties spotted a surfaced U-boat:
‘The pilot closed. Five minutes later, puffs of smoke rose round the submarine as she tested her guns. Then the Stringbag was within range, and the enemy opened a continuous fire with pom-pom and several cannon.
‘. . . Weaving between 1,500ft and 2,500ft, drawing in not more than half-a-mile and turning away again, most of the shells burst astern of them as the U- boat gunners overestimated the speed of the slow machine.’
The Swordfish successfully depthcharged the boat as it attempted to dive.
The U-boats were quite prepared to fight it out on the surface where their weaponry allowed, including using deck guns to finish off ships.
John Bennett, Matlock, Derbys.