The guerrilla war in Zimbabwe-Rhodesia is almost certainly taking a much larger toll now than the government is admitting publicly, probably as many as a hundred people a day.

In a country the size of this embattled one of 7 million people, the casualty rate is comparable to a million Americans a year dying in warfare.

The official overall death toll in the battle for power which began in late 1972 is more than 17,000 through July, but it is hard to find people outside the government who believe the figures.

A wide variety of sources say as many as 100 persons are dying daily in the war or from war-related causes. The vast majority are blacks, either civilians or members of the Patriotic Front guerrilla forces based in Zambia and Mozambique.

Considering that the war revolves mainly around the status of fewer than 250,000 whites -- the approximate equivalent of the population of Richmond -- it is a conflict in which many are dying over the fate of a few.

The government says that fewer than 200 persons a week are being killed overall. It does say the death toll has risen sharply, with almost as many killed in the first seven months of 1979 as in all of last year.

The official figures do not include the thousands killed outside the country in cross-border raids. Nor do they account for the untold numbers who have died because 57 percent of the country's 275 hospitals and clinics are closed as a result of the war.

British Prime Minister Margaret Thatcher said at last month's Commonwealth conference that 500 persons were being killed weekly. The major participants in drafting a settlement plan to be negotiated in London this month agreed that if this effort failed, the casualty rate could go only one way -- up.

If the estimate of 100 casualties per day is anywhere near the correct figure, about 35,000 persons are being killed a year. In the 10 years of sectarian violence in Ulster, fewer than 2,000 have died. A similar killing rate in the United States, which has 30 times Zimbabwe-Rhodesia's population of 7 million, would result in a death toll of more than a million persons a year.

Other statistics are just as frightening for the future of the country. The latest government figures show that 39 percent of the almost 3,700 schools in the country are closed because of the war and 360,000 students have been deprived of an education.

Last November, when only 27 schools were shut, a government official said the war "threatened to create a generation of illiterates" among Africans.

At the time, he said the one ray of hope was that the rate of closure of schools was tapering off. Nine months later, the rate has increased by almost 50 percent.

None of these figures, however, show what the war has meant to the lives of the people, particularly those living more than 20 miles from Salisbury. At about that distance from the capital, signs on highways advise motorists not to drive after 3 p.m. It is a warning most drivers -- especially whites -- take seriously.

A black who travels throughout the country running the remnants of youth programs tells of incidents where five-year-old children "instictively hit the ground and shout 'Take cover'" when a spoon is dropped.

"Life is on a day-to-day basis," said the man, who declined to be identified. "People simply feel thankful that when the sun sets they're still alive."

The war is even reaching down to the very young as the guerrillas use boys, sometimes as young as 10, in poorly trained groups called "mujibaks to move supplies and provide information about government security forces.

Although the guerrillas mainly operate with the support of villagers in the countryside, this backing is often grudgingly given. A white missionary tells of guerrillas coming into villages, taking all the food and then lounging around until they are eventually spotted by government forces and attacked. Civilians are often the main casualties.

It is not uncommon for a village of 25 families to provide food for as many as 90 guerrillas, not necessarily on a voluntary basis.

Just how involuntary the support can be was vividly shown by the government late last month when reporters were taken to the African compound of Pat Taff, a white farmer living in the Mtepatepa area about 80 miles north of Salisbury. The reporters saw something that has become all too common.

According to the military, guerrillas are maintaining a base about two miles away on tribal trust land reserved for Africans and had made their fourth visit to the farm in 10 days. Their basic intention is to force the African workers to flee and thus drive the white farmers from their land for lack of labor.

This time the guerrillas took to violence, herding the workers outside the compound fence and telling them to lie down.

"They then opened fire on us" and bayoneted those who were slow to hit the ground, according to Hamilton Sitanare, 30, one of the surviving workers.

A Special Branch police officer showed the results: seven dead, including an infant and a child. The infant was bayoneted to death on its mother's back. The back of a woman's head had been shot off, leaving a hole of about eight inches.

"I feel sick," the officer said as he uncovered the bodies. "God help the human race."

All the horror in this ugly war is not confined to one side.

The files of the Catholic Commission for Justice and Peace, long a thorn in the side of the Salisbury government, are rife with allegations from civilians of brutalities committed not only by guerrillas but by government security forces and auxiliaries supporting the government.

The auxiliaries, formed during this year's election campaign, often acted as bully boys for their chosen political party.

John Deary, head of the commission, said if his organization followed up every atrocity report "we'd be digging up shallow graves for three months at a time."

The incident reports, kept in a jammed filing cabinet, include killings, beatings, abductions, farm burnings and persons dying mysteriously while in custody.

The escalating brutality of the war seems to have resulted in agreement among white and black civilians on at least one point: People are sick of the war. From this despair has sprung some hope that perhaps the London conference, the next phase in the seemingly interminable Rhodesia negotiations, might bring an end to the suffering.

The slogan of the new Zimbabwe-Rhodesian government of Bishop Abel Muzorewa is, "The people want peace, that is what the people want."

A downtown Salisbury department store has the slogan on T-shirts in its window display. The store hedges its bets, however. Next to the first group of shirts is another group saying "Cheers Gook" superimposed over an African head with a gaping bullet hole in the skull.