342 THE FIGHT AGAINST YELLOW FEVER. 



Thus were established two secondary sources which became in 

 their turn two new centers of radiation — the Brazilian source and 

 the African source. This African source, which dates, as I have 

 said, from the middle of the eighteenth century, is located in the 

 Gulf of Guinea between the mouths of the Niger and the Kongo. It 

 is particularly in the region of Sierra Leone that the permanent en- 

 demic character of the infection is clearly manifest ; from here 

 have radiated most of the epidemics which have ravaged Africa. 



The Brazilian source is of more recent date; it was established in 

 the middle of the nineteenth century. In 1849 a single ship from 

 New Orleans, the Bras'd^ brought yellow fever to Bahia. From that 

 city another vessel, the Naixirre^ carried it to Rio Janeiro, where it 

 found all the conditions necessary for its naturalization — a low, 

 marshy ground, river deposits, an intense heat, and an excessive 

 humidity. So the disease took permanent root as an endemic; it 

 became a national disease. Finally it branched out from this new 

 center toward the interior countries, following, as usual, the courses 

 of rivers. Thus was produced the epidemic which in 1870, during 

 the war waged by Brazil against Paraguay, broke out in Assumption, 

 on the Parana, 1,200 kilometers from the coast, and with 30,000 

 victims spread as far as Buenos Ay res. 



Europe in its turn has been the object of many repeated attacks by 

 this terrible plague. The southern countries below the forty-third 

 degree of latitude have especially suffered. Spain was attacked for 

 the first time at Cadiz in 1700. The same port was infected from 1730 

 lo 1734, then in 1780. again from 1800 to 1804, and from 1810 to 

 1812. The epidemic of 1800 to 1804 instead of being confined to re- 

 gions along the coast climbed the course of the Guadalquivir and 

 gained the interior country: it spread to Andalusia and fell upon 

 Catalonia, with a total of 80,000 victims. In 1812 Barcelona was in- 

 fected by the ship Grand Turv^ hailing from Habana, and 20,000 per- 

 sons perished. Another epidemic l)roke out in Pasages in 1828. 

 From this date there is nothing to mention except two relatively mild 

 incursions of the plague — one in Barcelona in 1870, the second in 

 Madrid in 1878 upon the return of a Cuban regiment. Portugal was 

 seriousl}^ attacked at Lisbon in 1723, and lightly in 1750 and 1751. 

 In 1856 Oporto was the seat of an important epidemic which, brought 

 by two ships from Brazil, killed 7.000 persons. Italy, since it has 

 little maritime relation with the centers of contamination, has re- 

 mained almost entirely free from the plague. Nevertheless in 1804, 

 r;t the time of the Spanish ejiidemic, contagion spreading from Bar- 

 celona to Livorno caused the death of 1,500 persons. In 1883 a 

 patient arrived at Torre Annunziata and became the center of a slight 

 spread of yellow fever. 



