xMarch 1, \m.\ THE TROPICAL AGRICULTURIST. 
593 
ANTIMALARIA CAMPAIGN. 
The Boman correspondent of the Lancet has sent 
the following account of the systematic action of 
Italian physiologists in experimenting on the bites 
of mosquitoes at the cause of malaria 
The strenuous efforts now being put forth in Italy 
to combat malaria and tubercnlossis make it neces- 
sary to return frequently to these topics in order to 
follow the progress of the campaign against them. 
In regard to malaria the Acadeviia dti Lincei pub- 
lishes ihe first report of tlie experiments undertaken 
by Professor Grassi and others along the Battipaglia- 
Keggio line of railway from San Nicola Varco to 
Albanella, over a distance of some eight miles. 
The objects aimed at were two : (1) to prove that 
malaria can be contracted only through the bites of 
anopheles ; and (2) to find means of overcoming the 
practical difficulties that stand in the way of an 
efficient prophylaxis. Altogether 104 persons, in- 
cluding 38 children under 10 years of age, were 
kept under observation, all of them being railway 
employes with their respective families, living at the 
two stations and in various houses, 10 in number, 
along the line. The locality chosen, the Plain of 
Capaccio, is among the most unhealthy in all Italy. 
The persons selected for the experiment had all been 
examined during the non- malarial season — that is 
to say, before the anopheles had become infected 
and those found to be malarious had been treated 
with quinine. 'I'he preventive measures adopted 
were the protection of the houses from the entrance 
of mosquitoes by wire gauze over the windows and 
the wearing by any persons obliged to be on duty 
outside after sunset or during the night of a simple 
veil attached round the hat with elastic, and of 
thick cotton gloves with tight sleeves. All who 
could went indoors at sunset and did not come out 
again till after sunrise. It was found very difficult, 
especially at first, to induce the people to observe 
these simple precautions in the efficacy of which 
they had no faith, but, nevertheless, of the 104 in- 
dividuals experimented upon, excepting three cases 
of relapses which had escaped the previous treat- 
ment by quinine, not one has so far been attacked 
by malaria. This is very fortunate, for in spite of 
all precautions some anopheles succeeded in inflict- 
ing their bites, and although the proportion of in- 
fected insects is small (1 per cent.) one of these 
latter might easily have found its way into a house 
and inoculated some of the inmates. The better 
to supervise the experiment Professor Grassi spent 
three days a week on his field of operations, sleep- 
ing at the station of Albanella with open windows 
('covered, of couise, with the wire gauze), and the 
same was done, though for shorter periods by Dr. 
Martirano and Dr. Blessich who assisted him. 
While the subjects of the experiment thus enjoyed 
a complete immunity from malarial fever the other 
inhabitants of the sane locality, who may be re- 
garded as so many control subjects, not having 
been protected in any way against the anopheles, 
fared very differently, having, it is stated, been all 
attacked, even those living under otherwise superior 
conditions. Other similar experiments have been 
carried out by Di Mattei in the Val Savoja* and 
by Dr. Fermi and Dr. Tonsini on the Island of 
Asinara,t near Sardinia. The former place is 
exceedingly malarious, and the mosqnitoi s ii e 
numerous ; nevertheless, by the aid of wire g nza 
over the windows of the house, and the use r.f oil 
of turpentine on the hands and faces of the five 
inmates who carried out the experiment, the mos- 
quitoes were kept away, and no case of malaria 
occurred during a period of four months. Else- 
where in the locality malaria was raging. In Asinara 
the conditions are peculiarly favourable for testing 
» Annali d'Igie ic S^jer., fast. 1900. 
t Ibid. 
the practicability of entirely ridding a ^given area 
of malaria by destroying the mosquitoes infesting it. 
Dr. Fermi and Dr. Tonsini, by destroying the larvae 
with petroleum, and the adult mosquitoes by means 
of pyrethrum, chrysanthemum, valerian, and zanzo- 
lina, succeeded in exterminating anopheles in the 
island, and greatly diminishlug the number of 
culex pipiens. At the same time use was made of 
wire gauze over the windows of the houses to 
protect the inhabitants from being bitten, with 
the result that no fresh case of malaria occurred 
in the island^ a'thovgh in the previous year 40 per- 
sons had contracted the disease there. The experi- 
ment was carried out last year from June to 
November, and is being oontinued this season. 
The last number of Nature -also contains a notice 
of the work of Dr. L. Sambon and Dr. G. C. Low, of 
the London School of Tropical Medicine, in a part 
of the Roman C ampagna, near Ostia, where scarcely 
a person - spends a night without contracting a 
malarial fever of a virulent type. No quinine pr 
other drug was to be taken as a precautionary 
measure, but the investigators were to live in a 
mosquito-proof hut from an hour before sunset to 
an hour after sunrise, so as to avoid being bitten 
by mosquitoes, which only feed during the night. 
The experiment was planned to test the reality of 
the connection between malaria and mosquitoes, 
and the British Uedical Journal reports that it has 
been most successful. On September 13, Prof. Grassi 
visited the residence of the investigators with 
several other men of science, and gave his testi- 
mony as to the value of the experiment in the 
following telegram to Dr. Manson : — ' Assembled in 
British mosquito-proof hut, having verified perfect 
health experimenters amongst malarial stricken in- 
habitants, I salute Manson who first formulated 
mosquito malarial theory.— Grassi." So far as tha 
experiment has gone, therefore, the result is entirely 
satisfactory, and affords the strongest support to tha 
mosquito theory of malaria. Additional evidence is 
given by Dr. Elliott, a member of the Liverpool 
expedition sent to Nigeria some time ago to investi- 
gate the subject of malaria fever, who has recently 
returned to this country. He reports that the mem- 
bers of the expedition have been perfectly well, 
although they have spent four months in some of 
the most malai-ious spots. They lived practically 
amongst marshes and other places hitherto supposed 
to be the most deadly, and they attribute their im- 
munity to the careful use of mosquito nets at night. 
Another experiment arranged in connection with 
the malarial investigation in the Campacna is des- 
cribed in the British Medical Journal. Drs. Sambon 
and Low have shown that by avoiding mosquitoes 
they avoid malaria; but this is, after all, only 
negative evidence, and its full value can only be 
appreciated in connection with the actual production 
of malaria in a healthy person in this country by 
the bites of mosquitoes containing the germs of the 
disease. The evidence is now forthcoming. A con- 
signment of mosquitoes which had been fed on tha 
blood of a sufferer from malaria in Rome, under the 
direction of Prof. Bastianelli, was received in 
London early in July. A son of Dr. Manson, who 
offered himself as a subject for experiment, allowed 
himself to be bitten by these insects, and, though 
he has never been in a malarious country since he 
was a child, lie is now suffering from well-marked 
malarial infection of double tertian type, and micro- 
scopical examination shovrs the presence of numerous 
parasites in his blood. Full details of the experi- 
ments will be published in due course ; meanwhile, 
they must be regarded as affording the most strik- 
ing confirmation of malaria by mosquito bites that 
has yet been obtained. 
The number of the Lancet for September 29th 
also contains a paper by Dr. Patrick Manson on 
" Experimental Proof of the Mosquito Malaria 
Theory." — Journal of the Society of Arts. 
