160 
MALARIA 
1936) there were 16 relapsing eases and 
several relapsing eases (number not stated) 
observed in 1936 that were not included in 
the 120 cases reported for 1935. The origin 
and course of this malarial epidemic is 
rather obscure. Butts reports no new cases 
up to August 14, 1936, but only relapses. 
All infections recorded were due to P. 
vivax. 
The state health officer (Dr. Mahaffy) 
reports only 1 ease in 1937, none in 1938, 1 
in 1939 and 1 in 1940. 
A peculiar epidemic occurred, in 1934, 
in Aurora, Ohio, a small village of about 
1,000 inhabitants where no malaria had 
been known, at least since 1920. On Sep¬ 
tember 3, 1934, seven cases were reported, 
two of which had parasites (P. vivax ) in 
their blood. The publicity of these cases 
soon resulted in the discovery of 22 cases 
that developed prior to September 3. Later 
there were 10 new cases in September and 
5 in October, or a total of 37 cases between 
August 21 and October 23, or 3.7 per cent 
of the total population. The origin of this 
epidemic is obscure, though Hoyt (1935) 
reports a case of malaria in a house painter 
who had malaria in Florida and a relapse 
in May in Aurora (1934). Search for mos¬ 
quitoes demonstrated the breeding of A. 
punctipennis but not of A. quadrimacu- 
latus. However, A. quadrimaculatus was 
found in the houses but a dissection of six 
adults proved negative. As mosquito con¬ 
trol measures were started at once no 
further information could be obtained. 
Probably as interesting and as sharp an 
epidemic as recorded is one reported for a 
small section of the Elk River which 
empties into Wheeler Lake, Alabama. 
Smith (unpublished thesis 1939) investi¬ 
gated this outbreak and; his report may be 
briefly summarized. Tlie area is part of 
the T.V.A. impoundment of Wheeler Reser¬ 
voir. In this locality (Limestone County) 
not a single breeding place could be found 
before impoundment within two miles of its 
high-water line. After the reservoir was 
filled certain localities along the Elk River 
furnished favorable places for breeding of 
A. quadrimaculatus. A malarial survey in 
1934 (two years before impoundage) 
showed 22 cases in a small peninsula in 
this area. This land was purchased by the 
Authority and depopulated before im¬ 
poundage. 
During the summer of 1937 certain col¬ 
lecting stations in this localized area 
showed high mosquito counts and in Octo¬ 
ber of the same year came a report of a 
malarial epidemic. The area in question is 
populated by tenant farmers (%), and land 
owners (%). About one-third of the ten¬ 
ant farmers move each year, but in general 
the population is quite stable, the same 
people remaining year after year. Since 
the Authority had complete information of 
every house within one mile of the reser¬ 
voir it was not difficult to make a detailed 
survey. The entire population numbered 
842 in 176 houses. Blood smears were col¬ 
lected (in early October) from 743 of these 
people. Of these, 106 (14.2 per cent) had 
malaria parasites (68 with P. falciparum; 
38 with P. vivax). Case histories showed 
a much higher incidence in August, at least 
50 per cent of the population. The anti- 
malarial drugs taken by most of the people 
tended to prevent the showing of the para¬ 
sites in the blood. As malaria was not com¬ 
mon in this locality the case history records 
are of great value. In 1936 only 94 gave 
positive case histories, while in 1937 there 
were 370 with positive case histories and 
106 (in October) showed malaria parasites 
in their blood. 
What was the source of this epidemic and 
how to account for its severity (50 per cent 
of the entire population) in an area about 
12 miles along the Elk River and for a dis¬ 
tance of fully one mile on each side cannot 
be answered with certainty. Some 92 per¬ 
sons gave positive case histories for 1936 
and a number of tenant farmers from other 
endemic areas moved into the area that 
spring. The anopheline breeding in this 
area during 1936 showed an average weekly 
catch of A. quadrimaculatus per station 
(Nos. 15, 17, 18 and 19) of .25, 2.83, 2.58, 
and .06; in 1937 these same stations had an 
average weekly catch of 16.70, 15.86, 50.69 
and 10.04 of A. quadrimaculatus. The 
