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J. Health Conditions, continued

5. Epidemics

There seems to have been no epidemic outbreak between the founding of the royal fort at Tubac in 1752 and the year 1760. This gave the settlers a breathing spell to acclimate to the climate and local germs of the old Indian settlement.

a. Epidemic of 1760. In this year an unknown illness struck Sonora. The symptoms included lassitude and depression, loss of appetite and thirst, severe pain in the limbs, headaches and a feeling of heaviness and dizziness which made it difficult to remain standing. Those who forced themselves to stay on their feet threw the contagion off faster than those who went to bed, according to the Jesuit missionary Ignaz Pfefferkorn, whose value-system blinded him to the fact that those able to stay on their feet must have had a less worrisome attack in the first place. Fatalities occurred primarily among those already weakened by age or some other malady (Treutlein 1949:217).

The upper Santa Cruz River Valley Indian missions seem to have been affected by this contagion during January when Guebavi counted eighty per cent of its recorded fatalities for the entire year, Tumacácori thirty-seven and one-half per cent of its total and Sonoita fifty per cent (Santos Angeles de Guebavi, Libro de Entierros). The royal fort at Tubac escaped with no known fatalities, however, indicating that this epidemic was more deadly to the Indian populace than to the Europeans and mixed-bloods at the fort.

371b. Epidemic of 1765-1766. During February and March of 1766 the upper Santa Cruz River Valley Pimans were afflicted by an infectious epidemic which interfered with Spanish military operations.

This epidemic apparently began in southern New Spain during 1765 and spread northward. It reportedly reached Sonora toward the end of June (Treutlein 1949:217) although it did not strike the frontier missions near the royal fort at Tubac until February of 1766 (Santos Angeles de Guebavi, Libro de Entierros). Symptoms of the malady began with severe headaches and bodily pains followed by very high fever causing delirium in most cases. Observers abandoned hope for patients who vomited and regarded blood dripping from the ears and nose as a sure index of recovery. Sonora suffered heavy mortality during this epidemic which wiped out entire families and virtually depopulated some villages (Treutlein 1949:218). While the 1760 epidemic had probably been simply a severe virus infection, this contagion may well have been typhus.

In the upper Santa Cruz River Valley area the heaviest mortality occurred at Tumacácori where thirty-eight and a half per cent of all 1766 deaths came during February. At Sonoita the February mortality was twenty per cent of that recorded all year. At Calabazas it was only ten per cent and not above average. At Guebavi mission one-third of the recorded deaths during the year occurred during February (Santos Angeles de Guebavi, Libro de Entierros).

372These deaths raised the 1766 death rate at Guebavi above the rate for several previous years. Based on the beginning of the year population (Lafora 1939:126 & Santos Angeles de Guebavi, Libro de Entierros), the crude mortality rate at Guebavi was 101.7 per 1,000 population except for the epidemic. The crude epidemic mortality rate for Guebavi was 50.8 deaths per 1,000 population, making the total crude mortality rate for 1766 at this mission 152.5 deaths per 1,000 population.

Actually the epidemic mortality was somewhat higher than indicated and non-epidemic mortality was lower. This was because fatalities from the epidemic continued into at least the month of March with decreasing frequency, and because the disease caused secondary complications which showed up in patients who had recovered from the initial attack.

It was the extension of epidemic fatalities into March which interfered with military operations in the frontier presidial companies. Captain Juan Bautista de Anza had taken a detachment of his troops from Tubac and a body of thirty Piman Indian scouts east to join detachments from the forts at Fronteras and Terrenate for a month-long sweep through hostile Apache country, leaving Tubac late in February (Anza Mar. 17, 1766:109). Anza was forced to out short his campaign at three weeks because the epidemic broke out among his Indian auxiliaries and he feared the death of more of them if he kept them in the field with little protection and great exertions (ibid., p. 112).

373Two of the thirty Indians Anza had taken with him died as it was, indicating an epidemic crude mortality rate of 66.7 deaths per 1,000 of population. This was somewhat higher than the 50.8 per 1,000 at Guebavi Mission, but this much variation is not significant because of the small size of the samples. The two figures do indicate the approximate severity of the disease among the northern Pimans.

Recovery from the disease was slow and characterized by bodily weakness, aversion to meat in the diet accompanied by deep melancholy. The complications included sudden loss of sight or hearing (Treutlein 1949:.219).

c. The Measles Epidemic of 1770. As the year 1770 began the Indians living at the mission of Santa María Magdalena about seventy miles south of the royal fort of St. Ignatius at Tubac were developing symptoms of epidemic measles of a severe type. On January 21 the first measles fatality occurred, and the epidemic did not leave Magdalena until February 18 (Libro de Entierros de Santa María Magdalena de 1702). At least fifty-three and eight-tenths per cent of the total deaths recorded at Magdalena during 1770 were caused by epidemic measles.

At San Ignacio Mission epidemic mortality commenced on January 6, lasting until February 20. Measles fatalities made up sixty-one per cent of the 1770 deaths at San Ignacio. The 1770 mortality was up 181.8 per cent over 1769-nearly tripled (Libro de Entierros deste Pueblo de San Ygnacio... de 1697, f. 3-5v).

377As the year wore on the epidemic became general in Sonora (Arricivita 1792:416). The Gulf coast Indians resisting the great Elizondo military expedition were decimated about this time by a severe epidemic reportedly of yellow fever (Rowland 1930:214). Significantly this epidemic accomplished what two years of fighting by hundreds of regular army and frontier fort troops had not accomplished-the first significant surrender of hostile Indians in any important numbers. This occurred only after the contagion took its toll of the independent Indians. It marked the turning point in the war and the beginning of the end of Indian occupation of the desert area along the Gulf Coast and inland to the San Miguel River Valley. If yellow fever was indeed responsible for the epidemic among the hostiles, the total contagion may well have been dual.

This epidemic did not strike the upper Santa Cruz River Valley populace with nearly the severity it had at Magdalena. Unfortunately no data on morbidity in the Tubac area have been found, but the mortality records indicate very slight measles mortality. No deaths were reported at the royal fort itself.

At Guebavi Mission one-third of the deaths recorded during the year 1770 occurred during February but the proportion was only twenty-three per cent of the total at Tumacácori, eighteen per cent of the total exclusive of those killed by Apaches at Calabazas, and about seventeen per cent exclusive of Apache victims at Sonoita. While these figures are all 375above the ideal average of eight and three-tenths per cent per month, some of the difference may be due merely to sampling error in the very small numbers involved. The fact that thirty-six per cent of the year's total deaths at Calabazas (exclusive of Apache victims) occurred during March may indicate that the measles epidemic did in fact strike there but flared up primarily during that month (San José de Tumacácori, Libro de Entierros).

Quite clearly the upper Santa Cruz River Valley settlements as a group and the royal fort of St. Ignatius at Tubac in particular somehow escaped the worst effects of the measles-yellow fever epidemic of 1770. It came but did not kill.